Airport problem: self assigned IP address?
 

I'm using DSL, I've had it for about 4 weeks. For the past week or so I've been having a problem connecting to the internet wirelessly through airport after the computer goes to sleep and is rewoken(rewaken?). I get this message when i go to see the network status in the system preferences:

"Airport is connected to the network Sundance. Airport has a self assigned IP address and may not be able to connect to the internet."

For the first three weeks i NEVER had this problem, and now it shows at least once a day. I figure i might have changed something in my network preferences but i don't know what. I don't really know what dhcp or ipv6 or ipv4 is but it is set to "using dhcp" under the tcp/icp menu in the configure ipv4 section and configure ipv6 is off.

sometimes if i turn airport off for a few minutes and then on again the internet will work, sometimes if i don't turn it off it will work after a few minutes...???



any help would be great!!

:confused:

Did you turn on the firewall on your laptop (whatever is using an airport card)?
Do you have automatic reconnect set up in your Network Prefpane (Airport tab)? ["By default, join: Automatic"]

my firewall is on, but its been on for the past 4 weeks. also it is set to join automatic.

Try tuning the firewall off and putting it to sleep and waking it up. Just to see if it still self-assigns the IP.

firewall?
 

I'm having the same problem as Sundance - although I can connect at home, I can't connect at work. I'm on a Powerbook 15" that came with built in airport extreme. I can see the signal in my airport toolbar, it says I'm connected but browers can't find any websites.

How do you turn the firewall off?

Mike Russell

Well, it may be that you are connected, but you cannot get to any websites because you don't have a DNS server responding. Get your airport connection at work and try connection to this address in your web browser:

http://216.109.118.75/

If it works, the problem is DNS.

To make sure the firewall is off, open the Terminal and type this in:

sudo ipfw l

(That is a lowercase L after ipfw) If it returns anything except "65535 allow ip from any to any", then the built-in firewall is running. Turn it off via the Firewall tab in the Sharing prefpane, or by typing into the Terminal:

sudo ipfw -q flush

This does not account for any 3rd party firewalls apps that use 3rd party firewalls, suck as FirewalkX and NetBarrierX. You'll have to look at your documentation to find out how to turn those off, assuming you're running one.

If you get a 'self-assigned' IP address, of the form 169.254.xxx.xxx this means you are not successfully negotiating with the DHCP server to get an address.

This can be for a wide variety of reasons, but the first thing to try is restarting the DHCP server (in this case, the basestation). Another possibility is to check the security settings, and make sure they match exactly.

Also, none of you say what kind of basestation you have. Non-Apple access points can be a little tricky, mostly because of terminology differences and poor configuration interfaces and documentation, often web browser based.

Yes I am getting this 'self assigned' message but in an interesting twist of fate it turns out that the wireless base station here isn't running at present and I'm inadvertently trying to connect to some remote bozo nearby. (It was him popping up in my airport menu that started me off on the wrong track).
There's no WEP password or anything required, but it'd seem a bit cheeky to hunt him down and ask him to restart his basestation :-)

i have a similar issue, but it's kinda weird.
I have a g4 powerbook 1.33ghz 256MB RAM 60GBHD, OS 10.3.5
i had the computer for about 2 months before it started losing the connection after going to sleep. at first it was maybe once a week, then it got to like every couple days until it became every single time. I tried instead logging into another account and no problem. but if i sign into my primary account at all, even if i log out of it it will happen 100% of the time. i have no access to any "airport" 802.11 routers but my girlfriend has another g4 (only differences being her processor is clocked at 1.0ghz and she hasn't upgraded to 10.3.5, i think she has 10.2.x or something) and it's never done it in the 10 months she's owned it. it's a real pain in the ass to switch over to my other account when the thing i'm trying to do requires it, knowing i'll need to reboot if i want to use the internet.

I've got the same problem and I know it's not a firewall issue or a DNS issue. The problem is that my airport basestation (snow version) isn't giving out IP addresses. It happens to all 4 of my computers connected to the ABS. The only way to remedy it is to unplug and replug the BS. Any ideas?

ABS hard reset? ABS firmware update?

ABS firmware is 4.0.8 - the latest as far as I know.

The thing is, nothing's changed with my setup in the past few weeks. I've read reports around of others having a similar problem just recently. Odd to say the least....

Posted this over at Apple. Perhaps it will help. Still working for me.

Here's what I had on my 12" PB, and here's how I solved it.

Despite good signal strength, I would find that turning the Airport card off and then on, or sleeping and then waking up, would drop the connection. Upon reconnection, I would be 'connected to the network' but I would have a self-assigned IP. Nothing short of restarting the machine would allow a DHCP lease supplied IP.

How I solved it:

1) Shut down the laptop.
2) Remove battery.
3) Remove airport card.
4) Reinstall battery.
5) Start up the machine.
6) Log in as root. (You could also log in as any admin, but you will have to authenticate.)
7) Delete your com.apple.airport.preferences.plist found in /Library/Preferences/SystemConfiguration/
8) Use Onyx (or similar) to delete all caches, system caches, virtual ram caches etc.
9) Shut down the machine.
10) Remove battery.
11) Reinstall airport card, making sure it is seated properly.
12) Reinstall battery.

I can now toggle the Airport card off and on, or sleep and wake, and the Airport card will renegotiate an IP with the Airport Extreme base station without problems.

Hope this helps.

Step 7 makes sense. The rest don't. Glad it worked, though.

self-assigning ip addresses -- same problem?
 

i have the same problem where i can connect at work, no problem, but at home i can't. i have an iBook 12" and i would like to try step 7, only i can't find the com.apple.wirelesspref. or whatever it's called. i go to the library and preferences menu and there are lots of other com.apple.whatever files, but none about wireless preferences. also, i don't know what onyx and am not sure exactly which caches to clear or how. i would appreciate any input, sorry if i seem really ignorant to all of this but i just started using wireless ...

it would probably be useful to add that it is a shared apt i live in, and i'm using the base station of one of my flatmates. it's NOT mine and i don't know if it's apple ... plus, i'd rather not ask him to restart his basestation every time i want to use the internet ... if there was a another solution, i'd really prefer it.

also, thank you for having this forum; it's helpful just knowing it exists and that there are people who can help. i'm out of the country and don't have access to 800 numbers in the states, so this is the best way to troubleshoot. thanks for making it possible.

Thanks, Nic for your suggestion.

I haven't had a chance to try it, but I will (on 25 iBooks!). Reading this thread supports the idea that it's something on the wireless client (I'd been thinking it was the config of my roaming network) because I see many people having the self-assigned IP issue (while connected to a strong wireless signal) with very different network setups.

I've been going nuts with this problem (self-assigned IP) for weeks despite numerous calls to Apple, latest OS, updates, Extreme hdw, reading web articles 'til I'm crosseyed, etc, etc. For the long story, see my post at http://discussions.info.apple.com/we...Cv.0@.689c75c6

Just wondering why Nic felt it necessary to do all the other steps... anyone have any experience with trying step 7 only?

(I did an initial test on 2 identical iBooks which were both self-assigning IPs in presence of AEBS: I trashed /Library/Preferences/SystemConfiguration/com.apple.airport.preferences.plist on one, then restarted both. Both machines then connected to the AEBS. Inconclusive.)

Hi

The main reason I opted for the other steps was because merely deleting the preference file alone didn't do anything for me. My reasoning was that flushing the various caches and PRAM with the card removed would force the system to rebuild those caches cleanly, before reinstalling the card. Doing this as root often configures those changes at the base level. (If anyone remembers the constantly reappearing US keyboard layout issue in non-US keyboard systems, setting the options as root made them 'stick'.)

mbcurtin, you must look in the root library prefences (/Library/Preferences/SystemConfiguration/), not your user preferences directory (~/Library/Preferences/) for the file.

For the record, folks, my self-assigning IP issue is better but not completely reliable. Most of the time things work well. Toggling the airport card off and on will not drop the connection. Sleeping the machine and then waking it will usually result in a connection starting up again, but once in a while it will fail. Occasionally upon waking, the IP will be correctly assigned but there will be no transfer to the base station and I will have to restart.

What's the bash command for clearing the DNS cache? I seem to recall that did the trick upon waking. It might be useful to trigger a shell script to flush the DNS on wake.

David, I just read your message on the Apple discussions boards.

R.E. setting the base station channels, I would personally set them manually. As far as I understand it, 'Auto' will seek a channel with the least interference. Attempting this with my three base stations caused problems (intereference between the base stations and disappearing base stations.) I have had no problems with them all set to the same channel.

Self Assigned IP
 

"For the record, folks, my self-assigning IP issue is better but not completely reliable. Most of the time things work well. Toggling the airport card off and on will not drop the connection. Sleeping the machine and then waking it will usually result in a connection starting up again, but once in a while it will fail. Occasionally upon waking, the IP will be correctly assigned but there will be no transfer to the base station and I will have to restart."

I recently tried the clean up method listed in this thread after this problem had gradually got worse. Since performing the exercise my problem still exists. Almost every time that I wake up my machine. I have even had the situation where the connection comes up and it resets itself and self assigns an IP address. Shutting down airport extreme does nothing to solve the problem.

I am running a 15" PB G4 with Airport Extreme and 10.3.6 (as of this morning), previously 10.3.5. The problem has deteriorated over the course of about 4 weeks. I am using LinkSys 802.11b and 802.11g wireless routers at home and at work.

I am now having problems where the airport signa disappears for a moment and as a result the self assigned ip address gets setup and my machine is hosed. This happened between reviewing an other post on this site and doing a submit.

The icon is indicating at least 3 bars on my 802.11g link. I have switched to 802.11b and an alternative base station. Neither base station is providing DHCP. That is coming from another server on the network.

This is on a network that has functioned quite happily for 6 months. The only changes have been software updates to my Powerbook.

I used to be able to roam happily across multiple wireless networks. Now I have to reboot almost every time.

kind of off topic but:
 

hey mbcurtin, we are out of the country as well, and I would recommend the following for anyone who is living out of the US, but requires calling the states on a daily basis:

www.brujula.net - using a X-lite SIP phone with plantronics headset
www.skype.com - using the same headset.

Works like a charm, and only costs $.029 per minute.

Mr. Sonora

I am still trying to make sense of this problem with self assigned ip addresses.

I have 2 networks, 1 at home and 1 at work. These networks both have separate 802.11b and 802.11g wireless routers (all are linksys WRT54Gs) set in either b or g only mode. Both networks have a separate wired firewall that is actually serving up DHCP to all the clients on the network.

I have found that I am usually able to reacquire a valid ip address if I connect manually to the 802.11b access point. If I connect to the 802.11g access point I get a self assigned ip address. This seems to be consistent on the home and office networks. Since the access points are the same linksys devices with the same firmware applied and the DHCP for the b and g connections are coming from a common server on either the home or office network it would seem that it is the 802.11g airport extreme code when operating in 802.11g mode that has a more consistent problem.

This problem seems to have emerged since the August (?) update of the airport extreme drivers.

I'm thinking it's the update...
 

New poster here, though I'm experiencing the same problems - and it looks like there are pockets of people around in the same boat. Tried a lot of things on my 12" 867mhz, but in the end, it seems my problems started with my last update of the airport software. Not thinking there is much chance of going back. Anyway, my current solution is to leave the laptop alone, and after a few minutes it seems to pick up an IP.

Alright - here's a newbie type q - how do you log into the root? I'm the "admin" for my computer - and I don't see an option for such a thing.

I tried the entire procedure and it did not fix the problem.

Apple released a new Airport Update on 15th November. I am not using an apple base station and the updates did not seem to alleviate the problem at all.

If you're using a Linksys base you may want to check and possibly upgrade the firmware on it.

I'm using the Qwest-pushed Actiontec wireless DSL router personally.

Possibly fixed it for me
 

Well, I had been having the same serious issues until the latest upgrade from apple and having turned off IPv6. But all of the sudden the problem was back. Now it seems to have been fixed simply by upgrading the firmware on my stupid linksys router!

I thought I was going to have to try reinstalling the OS from scratch!

Hopefully it stays fixed this time.

i solved self-assigned ip address problem
 

hi there,

I faced a challenge for two days looking through web forums, etc. regarding this problem. i was able to connect to the wireless router which is connected to the dsl line.

then one day this stopped working.

what worked for me, is to try assigning your own IP address, like 192.168.1.20. then, go back to assigning IP through DHCP. this seemed to have worked and had the effect of "slapping the router around to give me a valid IP through DHCP"... without having to restart the wireless router.

sorry if this is quite vague but i just needed to quickly get the word out on what worked for me, i know this is a common problem from what i see on the net forums, especially recently.

problem related to security protocols?
 

i just set up my g3 ibook with an airport card (not extreme) with a linksys 802.11b router. (latest firmware all round)

straight away i got the self-assigned problem mentioned here. except that i would reacquire a valid ip address every few minutes for 10 seconds or so, until reverting to the dreaded 169.254.x.x perhaps someone can shed light on this? (i had group key renewal set on 3600s)

this morning i traced the problem to my security settings. airport seems to like wep (only checked 128 bit) but not wpa. first time up, the only issue was that the wep passphrase was not accepted so i had to type in the full key.

For the record, when I set up my network nearly a year ago, I struggled with self-assigned IP addresses for too long, then opted for fixed IP addresses. I have had no problems since, and find that firewall configuration is very simple.

(I have a DSL modem/router feeding to my AEBS, which is distributing to one wired connection, one wireless, and a separate wireless connection for a virtual PC.

My 2 cents
 

Tried all of the above, including the pulling the airport card etc...

It got even worse when my ethernet connection was giving me the same problem. 2 evenings of grief!

What worked was getting my ethernet connection working with manual settings, and then plugging those into the Airport settings. A simple screenshot is what keep on hand for future reference.

Finally!

Ps...
 

Just for laughs, I tried the hardware reset, then using the AirPort Extreme Firmware 5.5 Updater immediately after. It worked. Now I have the "luxury" of being able to use a DHCP setting instead of a Manual setting...

Similar connection problem resolved
 

After several months of trouble-free operation, my 12" iBook/snow Airport BS seemed to have lost its connection to the outside world. I connected to the Base Station with no problem, but not to the internet. Everything seemed in order; indeed, I'd changed NO settings, yet it appeared that the iBook wasn't getting DHCP properly. I think I read about 100 posts from various places, but ended up trying a simple one first: I unplugged & replugged the router (Linksys, wired). Problem solved. Hope this helps someone before you jump through too many complicated hoops.

The problem still exists. I believe it to be something in the airport driver on the PowerBook. I have rebuilt Mac OS X and reapplied all the updates. I have also installed an Airport Extreme base station and an Airport Express using WDS and a WPA key on my home network. I still get the same problem whereby on coming out of sleep I get a self assigned ip address.

If I connect a cable to the wired ethernet port I get an ip address assigned correctly. If I then switch back to the wireless port I can't shake the self assigned ip address.

I have upgraded the firmware on the Linksys firewall that provides dhcp services. I have also upgraded the firmware on the Linksys wireless routers that are acting as 802.11b and 802.11g access points.

Given that the same powerbook can acquire a correct ip address from the same dhcp server being used by the wireless airport card this suggests that the update to the airport driver software that occurred around august/september changed the way that the card is initialised. The airport extreme successfully gets allocated an ip address every time it is started up during a reboot but does not manage to get an ip address if the card is woken from a sleep or is powered off and on again. It is as though the reloading or reinitializing of the airport stack does not go down to a low enough level in comparison to a system reboot.

Rebooting everytime I move locations or reawaken my laptop is getting very reminicent of the days of Windoze....

Spoke too soon
 

Regarding my post (#34, above),I guess I spoke too soon. Today, again, I have no wireless connection beyond the Base station. Too bad; my wife thought I was a genius for a minute there.
I tried to upgrade the firmware on the Linksys router and was unable to even do that; it just wouldn't start. I did notice that the activity lihjts on the router occasionally faded to near nothing, then came back alive slowly. This made me lose my internet connection to even my ethernet macs temporarily. But the iBook wireless connection stays kaput.
Would just love some help. My wife will think you're a genius.

Don't neglect the possibility that your Linksys box is simply malfunctioning. Borrow someone else's box and try that if you can. Or just buy a new router/basestation - they are relatively cheap now.

Latest update on the search for a reliable reconnection....

Both the Linksys (home firewall/router) and Netgear (Office firewall/router) have been updated to the latest firmware releases. This on it's own did not resolve the problem. Airport Extreme and Airport Express have been updated to the latest firmware releases (Dec 20th).

I then went through and reviewed my startup software. I have removed PocketMac Pro from my startup and now only activate it when required.

I also saw a note in another forum that mentioned the UPnP setting. There appears to be no setting in the Airport configuration for this. However both the linksys and the netgear have this setting. I have set UPnP to enabled on both the DHCP serving firewalls (Linksys and Netgear for home and office respectively). I also enabled UPnP on the wireless Linksys routers that are acting as access points.

Since doing the UPnP enabled setting I have had greater success with avoiding the self assigned ip address problem. My next step is to reinstall PocketMac Pro in to my startup and see if that causes the problem to reappear.

Mark S

Self Assigned IP address problem
 

For what it's worth I have had the same problem for a week or so. I'm on a 15" Powerbook G4, 1.25Ghz, connected via Airport to a D-Link DWL 2100AP Wireless Access Point.
For the life of me I couldn't get the Airport to connect to the internet, and kept getting that "self assigned IP address" message appearing on my Network Status.
Just a minute ago I found this thread, scrolled down and saw that bit about trashing the Airport preferences file - and what do you know? It worked!!
Fingers crossed that was the only problem and that if it happens again, I'll be bale to use the same remedy and have it work again.

I've been having this same self assigned IP problem only I connect wirelessly at my local coffee shop, so I have no control over the base station. What's strange is that some days, it's not a problem at all and other days there is absolutely no way to connect. I've also noticed that my connection is much weaker than my friends with PC laptops (I have a iBook G4). This is so frustrating? Does Mac know about these problems? Any ideas for fixes?

p.s. I have sometimes found that forcing a manually assigned IP and toggling back to the DHCP works. And other times I can just wait a minute and it will connect.

Disconnect on Log Out?
 

I had this problem. Just now I found that checking "Disconnect each time I log out" or whatever from System Preferences->Networks->Airport->Options seemed to solve the problem nicely. This may be a fix for a different, much more novice problem (I'm new to Macs) but since I was looking over this thread for a solution, maybe it'll help someone else!

I have the same problem (self-assigned ip address 169.254.xx.xx), but with my Ethernet connection... It is intermittent and I can't figure out how it happens. When it does happen, I try to switch from DHCP to a manual configuration, but even then, nothing works! I have a D-Link router, and only one computer on the network (which includes many Macs and PCs) have this problem.

Have you tried to replace the network cable you're using?

Yeah, tried that.

Anyway, I tried something from another thread (lost the url, sorry). I think the problem came from the fact that botth Ethernet and Airport were activated and, for some reason, the computer couldn't have an IP address assigned to it. So I created two different settings, one for Airport only and one for Ethernet DHCP only. We'll see how it goes...

What's strange is that there's other Powerbooks configured with both Ethernet and Airport in the same configuration that work flawlessly... Grrrrr...

funny i stumble upon this thread...

Just last night I was at a clients house fix their wifi network. they had a netgear 802.11b router one ibook and one imac. Both of the computers were about a year old with airport extreme cards in them. in the neighborhood he lived in, i found several unsecured wifi networks and he was scared about his being secured. So, I totally reset the router and set up his security, which was limited to wep, because that was all his router supported.

So i secure the network install some print drivers and other things and finally get everything talking to each other over the wireless network and it works, and i have to reboot from installing the newest print drivers to his network printer, and then boom, right after a reboot I get a signal from the airport it connects and I can file and print share but i can't browse the internet. This was because the airport was getting a self assigned IP.

so i go into the airport settings and make it so his machines only log onto his trusted network and make it so it automatically connects everytime. then i reboot again to test it out, and same results self assigned ip address.

long story short, i am pretty sure it is a software problem. probably OS related. I did about everythig to troubleshoot it short of wiping out the HD and reloading the computer. Now i thought it could have also been a bad airport card, but having both go bad at the same time was questionable.

My other opinion is that it is the B router, and is not fully backwards compatable with the G broadcom chipset that is used in airport exterme cards. I think this because my ibook at home connects to my linksys wrtg54L with out a hitch everytime and gets an IP everytime and its a b/g router.

This b router is kind of old like I mentioned earlier and only had wep as its only security feature, so maybe the old routers need firmware upgrades to be more compatable with the g cards, otherwise just pony up and buy a new router, i did for 50 bucks off of newegg.com and I love the new router i got. I can broadcast secure signal through out my whole apartment, meaning I can now do wifi system link games on my xbox with my neighbors:cool:

Has anyone come up with a broad stroke...
 

...solution for this issue? I'm experiencing the same type thing.

I have a cable modem, its worked great for months- the the other day- nothing. Tested my friends PC on it- worked great.

I went to a repair facility- they tried their DSL- worked on my Mac- they said its my cable modem.

Went to use wireless- all other computers in the area work great, mine won't gimme anything. Keeps giving the "there was a problem..." message.

Went back home, tried on cable modem again, nothing- back at repair shop- they know nothing- very few Macs where I am...

Any ideas on how to solve this issue would be helpful! Thanks!

I am sure it has to do with software, since in most cases it was working fine and now its not. in my client's case they had upgraded panther to tiger all the way up to 10.4.6 with out ever wiping and reloading the system.

at least when i ran into this problem I am sure its related to some sort of OS issues.

I have been reading this thread for awhile -- having this problem myself when trying to connect to my wireless network at home.

I seem to have solved it (for now) by creating a separate Location. I called it Home. Now it works fine. We shall see. Before this, I only had one default locaton -- Automatic. It seems to be a problem of some sort of timing. My MacBook somehow decided too soon that the network was not available and get a self-issigned IP address.

If you are still having issues
 

If you are still having issues use this thread I am trying to connect the dots and consolidate the problem.

http://forums.macosxhints.com/showth...809#post315809

Tony D

Bad link?

I'm having the same problem w/ a G3 iBook using Airport (not Extreme, i.e. 802.11b) connecting to a 4-year-old Netgear wireless router. MacBook Pro is connecting to the router just fine (802.11g), although the router has been acting up quite a bit in recent months, dropping connectivity and requiring frequent restarts...

So try a new router - they're pretty cheap now a days.

airport problem may be solved
 

Today I logged onto my Macbook via an ethernet connection, then unplugged it and tried logging on wirelessly.
No problem for about 5 minutes, then the connection dropped again and I got the self assigned IP address.
I turned off the airport card, and plugged in an ethernet cable.

At this point, I looked at the airport base station utility, and for the first time the airport base station was listed. It never had been before.
I downloaded the upgrade software for the base station. The software restarted the airport base. I unplugged the ethernet cable, turned on the airport card, and didn't drop the connection the rest of the afternoon.

I don't understand why the Mac could do that to the router when the airport card was turned off, but, oh well!

potential solution
 

Im new to mac and perhaps there is something else going on
BUT I was having the same problem of the airport self-assigning the IP address.

I tried multiple solutions including "reserving" an ip address for a specific MAC address on the actual router (which is acting as the DHCP server). even this did not work.

Then I checked the "Make AppleTalk Active" and had the "Configure" option set to "Automatically". its the only thing that worked. Hope this helps.

I have the same problem on an iBook 12" G4 running OS X 10.3.9 and conencting to a Linksys WAG54G. The problem started a few days agao and coincides with an auto software update:
2006-11-21 12:12:43 +0000: Installed "iTunes" (7.0.2)
2007-01-05 21:39:44 +0000: Installed "Security Update 2006-007 (PowerPC)" (1.0)

From all the information I have reviewed this sounds like it is a corrupted prefs file or a software bug from the security update.

Buying a new router is not the solution.....
 

There is a serious problem with OS X and certain types of secure wireless. Look at the number of unsolved issues just on this board.

Buy a new router? I have 200 computers that have no problem with the router and 5 Apples that do. So are you saying a new router will help?

There has to be a solution somewhere.

I only run into the wireless problem when there is 128 Bit WEP . I actually bought an access point that was weaker on the encryption side just so I could get on my school network. NOTHING would allow my MAC to connect.

Although LINUX and WINDOWS connect flawlessly.

This is a BIG problem considering that most people are wireless now-a-days and they need a flexible solution.

This is only one issue. The fact that my MAC cannot see Windows shares is also bad. And lets not even talk about binding to the domain.

What is the most frustrating is that it is not a WINDOWS problem. Because if you just use BSD or LINUX the issue goes away.

So my advice keep posting. Until we get some answers.

Tony D
---
I will try the Apple talk thing now.

Same issue but some results
 

As most of you me and all of my students who have Macs have this self-assigned IP problem at school. Now most of the time I don't have it-- at home, most I-cafes etc.

So I bought a Lynksis-G access point and lowered the encryption from 128 to 64(both WEP). And it works fine.

It seems to be the 128 WEP. I had the school update the server to be Mac Friednly based on some docs released by Apple. BUt we have hundreds of access points around school and all the windows and linux wireless computers work flawlessly on them -- and on my 64 WEP as well.

So it must be an OSX issue.

Maybe someone with this info and more knowledge than I can make sense of it and find a solution.

The MACs are perfect when wired into the network and Static IPs do not make a difference.

Ideas?

Tony D

The passwords are handled differently for "128 bit" and "64 bit" WEP.
So you need to make sure that you are entering your password correctly.
And of course it would be much better to use WPA instead of WEP.

Example?
 

Can you give me an example? Please understand there are over 600 PC's on the network and about 300 wireless laptops. SO everyone is just given the same exact WEP key. I have nothing to do with it. It isn't in my power to change it. Should I be asking for it in a different format? Here is what I am given (if anyone is in Dubai you can come by my school for free wifi)

Daaap$2170912

SSID Hidden: WIFI001

Is WPA better for everyone ? Opinions?

Thanks I feel like I might be onto a solution.

Tony D.

See the "AirPort client to third-party base station" section of this Apple doc:
http://docs.info.apple.com/article.html?artnum=106424

APIPA Addressing, ZeroConf, and self-assigned ips
 

I skimmed over the post but only saw one posting (number 7 from one of the site admins that seemed to come close to describing what is going on when you get a self assigned address 169.254.xx.xx.

When a client is unable to talk to the DHCP server or get responses, etc., the client assigns what is called an Automatic Private IP Addressing address (APIPA for short, Apple refers to this as ZeroConf instead)

What you have to do in in Windows is go to the command prompt and put in these two lines:
IPCONFIG /release [hit return]
IPCONFIG /renew [hit return]
That will force the client to send another request to the DHCP server for another address. Also, if it doesnt work, there could either be a problem with the router's built-in DHCP server or the server on another machine hosting DHCP service. (if others on the network are having trouble the same way- definitely a good indication of there being a problem with the server. - If not- troubleshoot the NIC or wireless card)

This used to totally drive me nuts when I would take my iBook to a cafe I used to go to. Here is the deal with Apple: in the Network panel with the Wireless card settings, it has a release/renew button, but IT WONT HELP! =(
I just came up with this Macintosh CLI fix which may or may not do the same thing I was saying to do on a Windows machine:

Open Terminal and type:
sudo ipconfig set en0 BOOTP (hit return)
ipconfig set en0 DHCP (hit return)

What this does is it tells the Mac version of IPCONFIG to detach itself from it's network bootstrap and point it at a DHCP server and go LOOK STUPID to the internet connection. It may not work in all situations, but this may be the only command line equivalent to force what that DHCP renew button is supposed to do but alas never does.

Anyway, I guess I should explain "why the hell would they make the damned thing have an IP address that doesn't #@$&* work?!?!" Well, remember that the message System Prefs>Network says is you wont be able to get on the *internet* with that address. That is the point- sortof. In principle, since the DHCP can't give you an address to get on the internet (is unable to respond to the request for whatever reason), this APIPA/ ZeroConf address is supposed to allow the client to be able to talk to LAN resources in the office (for example) so that people at the business can still talk to the local servers and keep working until the DHCP problem is resolved. I don't entirely trust APIPA addresses to actually do that though.

I hope it helps!
Tristan Mendoza
Austin, Texas
Penniless Sysadmin

Airport Problem: self-assigned IP address?
 

(We just power-cycled the Airport Base Station, although that might be inconvenient in some situations). Has anyone tried the suggestion(s) in http://docs.info.apple.com/article.html?artnum=106879 from way long ago?

Bill

My bizarre fix...
 

I've been having the same problem on and off and it's been driving me nuts...

BUT I FIXED IT...!

My fix makes NO sense at all though.
I have two external drives, a recent Lacie (firewire) and a new Seagate (USB)
if they're both plugged in, my airport goes off air!

If I unplug them, and restart the MacBook Pro, then all is fine and dandy!

Can someone explain THAT one!??

cheers,
matt
:confused: :confused: :confused: :confused: :confused:

Same story, late onset
 

My G4 Powerbook did not have this problem, not even once, while I was running 10.3. I've had periodic connection issues with our Netgear router, but since those took the G4 tower connected via Ethernet out as well, I assume those were real router probs, not wireless. I've roamed onto wireless connections in many places over the US, and also in Europe and Australia.

Since I installed 10.4 I've suddenly had this problem when trying to roam onto wireless networks in several different places. However, the Powerbook still recognizes my own wireless router, and has sniffed out at least one wireless router on the road.

This afternoon I fired up the PBook in Albuquerque airport, which has free WiFi. Up popped the box telling me that none of my preferred networks were available, but would I like to join this network called "sunport" (or whatever). I said yes, and the the little Airport icon shows full-strength. But I can't get a browser to go to any website, even the obvious ones like Yahoo. Internet Connect says I'm connected to "sunport". In system perferences I get the same information, that I'm connected to the internet via wireless network "sunport". Except that functionally I'm not; I can't get to any internet site.

So what did I break by installing Tiger? This is most frustrating..

I had a similar problem, and it happened after a set of changes I'd made to the server. This are what helped (of course after trying all kind of things): reset PRAM (don't know why?), and removed all my Locations (I had setup a 4-5 different configuration/locations) and started with automatic again. and that did it!

Solved
 

The solution for me was to lower encryption to 64 bit instead of 128

Here I was going to read the news before I went to bed and ended up spending the next hour trying to get wireless working. I'd never had a problem before that rebooting the router wouldn't solve, but something must have happened in the last week since I'd tried to go wireless (haven't been taking the Mac Book Pro mobile lately). I'm guessing there was an Airport update that could have messed things up, but I also did just upgrade my mini, which is on the same network, from Panther to Tiger, so who knows if that decided to steal some settings from the MBP.

Flipping it back to 128 caused it to die again, too. Ridiculous since I've been running that same router with various wireless Macs and PCs at 128 for the last 3 years, including having run it with this laptop for the last 4 months.

Hope you can all help me PLEASE! I have a new MacBook Pro (bought in January this year) running 10.4.9. All was well for ages. Worked like a dream and then suddenly it had trouble getting conneced to the internet. The connection showed up as working fine but pages wouldn't load in Safari and if I look at the network status it says "airport has a self-assigned IP address and may not be able to connect to the internet". The same thing happens if I switch off the aiport and plug into an ethernet cable (which previously worked fine).

What is going on? Please help. I switched to Mac from PC and was so happy and now I just wish I had stayed with a pc.......

http://docs.info.apple.com/article.html?artnum=106879

this worked for me...

Airport Problem: Self assigned IP address?
 

With both wireless and ethernet down and Network PrefPane saying DHCP server (AirPort base station) is self assigning IP addresses. I tried all the suggested fixes including Apple’s DHCP lease renewal (106879) advisory to no avail.

Here is what worked for me with the following configuration: MacBook Pro, Airport Extreme (7.3.1), 4 computers connected via D-Link Gigabit switch to the Airport Extreme Base station. Latest OS on all. I did the following:

Open Airport Utility (in Utility folder) > click Internet > select Internet Connection > then under Connection Sharing>scroll down to “Share a public IP address” > Press Update and there you go. I didn’t even have to restart the modem, base station or the switch. All 4 computers were once again on line.

Dave

Craig Arko's suggestion from 11-17-2004 (almost four years ago!) on page 2 has just solved my problem.

This was my situation: Windows XP Home Edition SP2 desktop was the main computer, hooked to a Linksys Wireless-G WRT54G v5 router (and a Comcast Motorola Surfboard SB5120 Modem). My Macbook Pro (10.4.11) could connect to the Internet on all outside networks, and could see full bars/reception from the home router, but got the "AirPort self-assigned IP address" address and a yellow dot on the Network page.

This problem was frustrating because the message suddenly appeared late last year after months of flawless operation. Then, it re-emerged another month or so later after I thought I'd fixed it by restarting the router and modem.

We'll see if this sticks, but it's very encouraging because the new blackout roughly corresponded to the March 2008 firmware update. Make sure if you have linksys that the firmware is up-to-date!

I'm having the identical problem.

I have just set up a netgear wg602 v3 router. I have two computers with me, a macbook pro 2.4 ghz and a macbook. Both bought around march - april of this year.

One connects to the wireless network fine. The other gets the self-assigned IP problem. Both have all software updates available to them.

I have attempted to change the encryption settings from WPA/WPA2 to WEP and decreasing the bit encryption from 128 to 64. The good computer always gets on and the bad computer always gets the self-assigned IP problem.

I have trashed the airport preference file in system library folder. I have reset the PRAM. The bad machine connects fine on other wireless networks within the past 24 hours. I did a factory reset on the router and updated the firmware. Still same problem.

If anyone's curious, my ISP is Cox, if that might be relevant.

Self Assigned IP address
 

After troubleshooting so many of these problems, it appears that many macs don't like the ten digit passwords that come with the all in one 2wire routers. By changing the WEP key on the router to a 26 digit combination in lieu of a ten digit combination, this usually resolves the problem.

One more suggestion (that worked). I often have this problem with wireless connections from my Macbook (10.4). What fixed it today was to open the Keychain utility and delete the entry for the wireless connection that was giving me fits. Then I got to re-enter the password and, in effect, start from scratch. In fact, it turned out that there were multiple entries for the same router which may have been aggravating the problem.

self-assigned ip solved
 

I have been struggling with this problem for a couple of days and it was driving me crazy. I have tried all of the solutions above-mentioned with no success.

The problem came across after trying to find a solution to another problem I had with my Time capsule: an IP conflict which made me drop the connection every 10-15 seconds. After I solved it (it turned out to be because of the router configured wong - my dsl company (tele2) gave me the wrong parameters by phone, I checked on their web site and got the right ones!!!!!)

This is what worked for me: after deleting the plist file, restting pram deleting the keychain with no success, I chose to do a assisted configuration of the interet (system pref - network - assist me... - assistant...). I previously had location set to automatic and created a new one with the "assist me..." feature and this solved it immediately, I finally got a correct IP address assigned again!!!

I hope that this helps someone else - this is my first post, I thought that it was about time I could help someone else after getting so much from this site!

I FOUND A SOLUTION THAT WORKS!!!! First a little back story.

Got my Mac Blackbook and the wi-fi worked great from my Linksys wrt54g2 router. Moved to Germany and into an apartment and my connection issues started happening. My MB would connect once then loose connection quickly and would only recover connection if i either closed and re-opened my screen, or re-connected to my network... then it would drop again before my next page turn.

After multiple days of research I read about SOOOO many others having this issue and the fact the Apple pretty much refused to acknowledge the issue. It seemed that sometime near the OX 10.4.2 update the airport driver got fubar'd leaving all those with Intel based macs wi-fi connects messed up.

Some of the solutions i read about and tried had to do with changing my WEP connection to WPA. This did not work, but i left it as WPA as my research finds it a more secure connection. I also read about and tried setting my Wireless RTA Threshold in my router to 256 from the *2432 default. This as well did not work, though I have left it at this setting as it seems to be the best value for MAC's connecting over wi-fi. This is not true for PC's though so be careful.

More research, more research, o' my brain hurts and my patience is wearing..... then BINGO!!! I found a thread about connection issues that pertained to MB's not connecting to local-network printers. The poster mentioned that MAC's seem to have a hard time connecting to networks that had more than one wi-fi network present. This is my issue i thought. I have 8 in my available connections now. In my old home I had just mine. So i followed the directions suggested and it has now been 2 weeks of 100% perfect wi-fi connections.

Below is the excerpt from this page, http://www.macintouch.com/readerrepo...topic2005.html (Do a find for “Little Snitch”). The program the writer talks about is called Little Snitch found here, http://www.obdev.at/products/littlesnitch/index.html. It's a $29 dollar program, but in my mind its well worth it to make my $1500 Blackbook work!

This may not be the Apple Fix we have been waiting for them, but its completely working for me.

note . . . i know very, very little about networking but know how to trouble shoot and just solved this problem on two of my macs. people in this thread had luck with changing their router settings so i tweaked some of my router settings. that did the trick. here's the hardware involved:

comp 1 - Mac mini PowerPC
comp 2 - MacBook Intel Core Duo2
router - D-Link DI-524
cable modem - Motorola SB5120
isp - timer warner cable

my previous router settings:

auto select channel
open system authentication
64bit WEP

new router settings:

channel 6 (a static channel)
shared key authentication
128bit WEP (<- after this change my macs started connecting)

now both macs connect fine. i've tried multiple restarts and sleep inductions on both machines and both are now consistently connecting. hope this helps some1.

btw thanks 2 all 4 making this a great forum

FYI, just this week Apple put out an Airport update specific to Intel based Mac's that covers issues of connections in locations with more than one wi-fi signal. FINA*UCKENLY!!!

@dubcee - glad you're up and connected.. maybe it was the update though?? your router settings are pretty standard.

i updated profusely on both macs to no avail. after changing the router settings then things connected. mayb a combination of the update and slapping the router around?

I must say, this is one impressively old thread!

I'm experiencing a similar issue when connecting my G4 iBook to the WiFi at the hotel I often stay at. My laptop works fine at home, and in the office, but occasionally gives me a self assigned IP address on this total open network.

Like others I thought I'd got it working be switching the wireless on and off, or assigning a fixed IP and flipping it back to DHCP. But the solutions do not work consistently.

Anyway, I noticed the following errors were appearing in my system.log during each connection attempt. Do they mean anything to anyone?

Nov 5 00:05:09 iBook airportd[128]: Error: process_command_dict() failed
Nov 5 00:05:10 iBook airportd[128]: Error: Apple80211Associate() failed -6
Nov 5 00:05:10 iBook SystemUIServer[102]: Error: airportd MIG failed = 5 ((os/kern) failure) (port = 48723)

Cheers,
Hugh

I just had this same problem and got an immediate solution from a netgear support forum.

I have a Macbook running 10.5.5, connecting wirelessly to a Netgear router.

In Network preferences, with AirPort selected, under Advanced settings, TCP/IP tab:

1. I changed 'Configure IPv4' from 'Using DHCP' to 'Manually'

2. Entered IP address: IP 192.168.1.200
Subnet mask: 255.255.255.0
Router: 192.168.1.1
(You may have to tweak these settings to match your network. Check your current router configuration.)

3. In the DNS tab, I added 2 DNS servers:
4.2.2.1 and 4.2.2.2

Cleared my problem up immediately. Hope this helps.

I think I've fixed mine now.

I deleted the Airport service from the Networking section of System Preferences, and then added it back. It worked last time I was staying at my hotel with the troublesome Wireless.

Interesting thread. I often fly EVA and use the free WiFi they have in their lounges. In the past, these free WiFi connections have always required a WEP (?) password which they supply when you enter.

I was in the lounge at LAX last night and was told that passwords were no longer required. OK. I sat down, the Mac found the network and connected long enough to download a few e-mail messages and then, that was it. Disconnected, never to connect again. The networks (2 of them) would appear and then immediately disappear in the Airport menu item. iStumbler showed steady strong signals from both networks. Every one of my laptop toting fellow travelers was able to connect, including a number of Mac users.

I tried turning the Airport card on and off. I tried rebooting. I tried disabling/enabling TCP/IP. I tried turning IPv6 on and off. I tried setting up a new location. I tried letting the "Assist me..." wizard establish the connection. It failed, claiming that a password was required.

The log is full of entries like this:

I'm now at the EVA Lounge in Taipei. It also has switched to wide open WiFi networks. But, obviously, I'm able to connect here with no trouble at all.

So, what do I need to do to make my G4 PB (10.5.5) connect at LAX?

I am not sure if this is the best thread to ask this question but I couldn't find the answer anywhere else!
Our household runs Macs and we use airport for our internet connection. One of my friends sometimes comes over and he runs a PC - we can't connect him to our airport connection. It won't even find it on his computer. Any advice? At the moment he connects to our unsecured neighbors connection but it is slow!
Thanks

I thought I would reply to this as wireless connectivity seems to be an issue with Macs, and yes I think part of it is the driver for the Airport card itself.

I would like to state that my MBP works pretty much every time with my home wifi network with out a hitch, but its when I get to work with my work's enterprise wireless network I see tons of issues. The basic repeating offenders are:

• *Self assigned IP address
  *Loss of encryption key in Keychain
  *Takes minutes and minutes of manually requesting a new IP to actually get one

I have reproduced this problem in both Tiger and in Leopard with our 1:1 macbook deployment at work. It happens all the time. What I see is if a client machine goes off campus and goes home for the night and get a 192.168.x.x IP from a home router it works fine, and the Airport card seems to prefer B/G radios over A. It will try to connect to the weakest B/G/N signal it can totally ignoring a great A radio signal. We of course run strictly A radios for many reasons. Then when the client machines comes back into our network it wants that same 192.168.x.x IP and is asking for it from the controllers which dish out DHCP. The controller of course says no, that is not a valid IP, we use 10.x.x.x so here is a new IP. The Mac client says no I don't want that IP gimme the 192.168.x.x and this will go back and forth for several attempts until it completely times out and the IP comes self assigned.

During this process I have seen encryption keys show the wrong passwords, but then again, I guess I can't rule out user interaction at that point. Perhaps my users are just randomly trying passwords to get back on the net I don't know.

So, since this was a head ache last year running Tiger and this year running Leopard I have seen a bit of a light at the end of the dark tunnel and it is the 10.5.5 update along with the Airport Extreme update, which says improves connectivity in large roaming networks. That is the only description of the update but I have seen an increase of clients on line (an all time record actually) through ARD admin this last two weeks at work. The Airport Extreme update requires 10.5.5 so I had to push out the 10.5.5 combo updater to all my clients as well as the airport update. It seems to actually be fixing these issues.

In the update I also added an update of encryption we are trying out as well and it seems to pick up better than the old WEP key we were running.

I had a similar problem with these same thing at my old work but instead of Cisco we were using Trapeze, and they also said it was driver issue.

I think when you go roam from network to network and when it requests an IP it will request the last one that it had (which is standard DHCP procedure) but the Mac client is kind of a little brat about it and refuses to take another valid IP and the handshake times out leaving the client with a self assigned IP. This is just my guess as I am not a developer or system's engineer, I am just a sys admin who happens to use this stuff frequently. The 10.5.5 update along with the new Airport Extreme update seems to definitely fix connectivity issues. I have already seen about +200 clients online at each building. So, instead of having an average of 400-500 clients I am seeing over 600 clients online at once now, and I have never seen any building have that many on line at one time. So, I think it is a safe assumption that those updates fix roaming issues with WiFi networks.

Of course upgrade at your own risk because 10.5.5 while it may fix your wifi issue it may break something else.

Different problem...
 

Hi guys, I'm experiencing a bit of a headache trying to get my internet to work. I probably have the most disgusting setup going on at the moment, which may possibly be one of the issues going on.

Anyways, I have an Airport extreme base station (that newer square-ish type), and I am trying to connect my Macbook Core Duo to it with an n connection (Core Duo's do not have n-draft on them to my knowledge, it is Core 2 Due chips or something) So I have inherited a Linksys USB N-Draft adapter, the WUSB600N. Using [http://forum.insanelymac.com/index.p...wtopic=131932] I've been able to successfully connect to the router, but now I'm experiencing the self assigned IP address.

USB Ethernet (en-2) : USB ethernet (en2) has a self-assigned IP address and may not be able to connect.

As stated in an earlier post, my IP is currently 169.254.xxx.xx, which means it's self assigning an IP. Hard resets will not reset it, and when I go into Network Utility and do the Ping, I get the following:

ping: sendto: No route to host
ping: sendto: Host is down
etc
etc
etc
100% packet loss.

I'm very far from computer savvy, so I really don't know what to do.

My current setup is the router, which connects do a D-Link 10/100 5-port gigabit switch. That in turn connects to an Airport Express (what i am currently using for b/g connection speeds), as well as the Airport Extreme, which is running in 5ghz n-draft only. I was hoping to use the Linksys WUSB600N to connect to the network, which appears to be successful, but now the airport extreme won't connect to the internet despite the green light. Any help would be much appreciated!

Why so many wireless routers? Why not just use the Airport Extreme and set it b/g compatible mode.

Also, which device is doing the IP address serving? Your router? The Airport Extreme?

I don't think you need the USB network adapter.

FYI, I upgraded my MB wireless to N. It's not that hard.

After trying every conceivable workaround (mentioned here and elsewhere including zapping PRAM, repairing permissions, repairing disk, resetting/rebooting FIOS router, etc.) to get rid of the "self-assigned IP" problem, one or more of the following solutions worked for me:

1) Changed the default WEP (40/64) 10-digit password (the one that is automatically assigned by the router when it's reset) to something else.
2) Under Network preferences (OSX 10.5.6), used the "Assist Me" function. This brings up a new "authenticating" message that was not there before.

So far getting great, stable wireless connection (since last night). Will let you know if anything changes.

Self-assigned IP
 

Hey all you tech guys out there, I have a good one for you that I have not seen at any of the other mac help sites(macrumors/apple forums) or here.

I am a college student that has access to wi-fi and ethernet cable internet. I was able to connect to the internet all year with no problem. I went home for christmas break and used the wireless internet at my house for about a month. I had a linksys router at home and everything was fine. I came back to school and set up my MacBook at my desk. I tried my ethernet and my airport and both of them give me a self assigned IP address. I have read ALL post on the above 3 sites on the problem and none of the suggestions have helped. Mine is a unique situation too, I receive my internet from a third party provider i.e. they set up the internet at our school and run cables to all rooms as well as provide wireless access points across campus. I do not have access to the router or any of its info. I called my ISP and have talked to all of their tech guys and none of them could offer any help. I have talked to Apple relentlessly and they had NO help either.

My friend can connect to my ethernet jack with his Dell Vista run laptop and connect immediatly. Another weird thing is that my XBOX 360 will not get an IP address either from the same point and it also assigns its own IP address. The same one that my Mac provides. I find this weird

I have honestly done EVERYTHING possible, firewall, firm ware erasing, assist, taken battery out, deleted key chain etc. I do not have access to the router as you know and my ISP says that it is not their fault and they cant help. If I have left anything out please let me know to help you. I desperately need internet or I have to walk down the hall to use my friends. Some other post have suggested reformatting the macbook and re-installing Leopard. I saw that this did not help some people though. With my luck i know it is sure to not help.

p.s.- I have all of the updates released by Apple in the past year

PLEASE HELP!!!

Drew

I am having the same problem as Drew
 

Let me start out with saying I have an imac os10.5.6.

My apartment has wireless access points set up by my ISP. Before winter break I was able to connect and had no problem. When I returned yesterday I was no longer able to connect to the access points. I can connect to an unsecured router someone in my area has however when I try to connect to the access points provided by my ISP I get the "self-assigned IP" message and am unable to connect to the internet.

My ISP spent 1/2hr-hr here yesterday and they are clueless (Completely PC people). The tech said he was going to go talk to his boss and see if they could figure things out and that he would call me today. He has not called me back yet.

I have followed almost all the steps listed on other forums but no avail.

I did upgrade to 10.5.6 over break. Is this the cause?... I know it messed with the local network at my work over break causing people to not be able to save to the servers, but it didn't mess with their internet.

Thanks,
Art4Me115

Hi guys,

I've been having the "self assigned IP" problem now for a bit. It all started when I let the battery run down, and I've been working with it now for a couple of weeks (except it affects ethernet AS WELL as airport).

I've found a temporary workaround. Go to Security in network preferences, and select firewall. Then select "allow all incoming connections". Go back to the preference pane, and select network. After about 15-20 seconds, it DHCP should assign a good IP. Then go back and reset your firewall.

Works ok, but if your Mac goes to sleep, you need to repeat.

Fd

same problem
 

hi I have had the same problem with increasing frequency. I have trashed my airport settings etc and changed my network preferences, and reset keychains it did work for a period. but the problem is now back. there seems to be no quick fix for this problem. sometimes my computer connects by itself but often not. it driving me bananas!!! :confused:

So I've just moved into a place with wifi but my computer isn't picking up on its signal at all. I know the wifi works because my roommates are on it. I know my airport works because I was just using it at another location today with no problems. So why the heck can I not get on to this particular network? It doesn't work when I try to add it to preferred networks. Can anyone please help me?

What model of Mac do you have?
What version of OS X?

Great trick!!!!! Thanx a million!
I had the problem that I could log on to skype wityh no problem but none of my browsers would connect to the internet (firefox, safary, netscape). After deleting the com.apple.airport.preferences.plist abd restarting the computer it worked again. I'm sooo reliefed!!!
Nic

802.1X OS Problem Self-assigned IP
 

I am in the process of reinstalling OS X 10.5. I can connect at home just fine but at work, where we use 802.1X, I often have trouble. My Vista machines always work in any environment. Vista and XP seem to be an order of magnitude more fault tolerant than OS X when it comes to wireless networking.

BTW, I have tried every solution listed previously and none have consistently resolved the issue.

I sure hope Apple "really" owns up and fixes this problem soon. Blaming the router, even if it might be true, is not a solution when other computers work flawlessly with the "defective" router without issue.

I have to say at this point I am bitterly dissapointed with my Mac experience. If I didn't need one to build apps for the iPhone I wouldn't waste my time.

Downgrade To 10.5.2 Seems To Fix
 

It was a pain but I installed from DVD to get back to factory shipping 10.5.2. So far this seems to have fixed my issues with connecting over 802.1X. The 802.1X screen is quite a bit different from 10.5.6 so if I don't have any problems over the next week or so I think we have to conclude that one of the Apple OS updates is the source of the problem.

I'll keep everyone posted.

Downgrade 10.5.2
 

Still don't see my previous posts but guess since I am new will take a while to be posted.

I was having self-assigned IP problem but only at work where we use 802.1X WEP. On top of that I only have trouble with certain access points.

That being said none of the Vista or Linux based machines ever have trouble even though my MacBook always struggles. So much for "it just works."

I have reinstalled 10.5.2 and so far this seems to have sort of fixed the issue. Previously I was running 10.5.6. I find that I still don't get an IP address automatically but have to select "Join Other Network" every time after I delete the WEP certificates. I am not sure what this indicates. Note that even if I tried "Join Other Network" after deleting certificates with 10.5.6 it still would not work.

While it is a pain to have to go through these gyrations to get on the network it is still much better than not being able to connect.

As long as this setup continues to work consistently at some time I have to conclude that the problem is with one of the updates between 10.5.2 and 10.5.6.

Airport problems
 

The lalest problem i have is with a brand new MacBook - Airport on it says "Self assigned IP" which BT doesn't accept - so I'm affectively blocked... How do I stop my software from self assigning when I don't want it to?

Change MTU to 4200
 

Okay.

As you can read from my previous posts downgrading the OS to 10.5.2 solved the problem.

However, since I use this as my iPhone dev machine I had to upgrade and wound up with the same problem.

However, as of today I think maybe I have found my solution.

I don't think that this will help everyone but my MacBook is back to flawless operation and seems even faster. My Windows XP virtual machine is considerably more snappy.

The thing I had to change was.... make the MTU on the Ethernet setting for the Airport 4200 instead of 1500.

This makes no sense since 1500 should be a good value but at this point I don't care why it works.

Like I said before my problems only happen at work where we use 802.1X with WEP.

Why 4200? I remember seeing someone else mention this in connection with 802.1X but can't remember where and Google searches have not turned up anything.

So, for what it is worth my problem seems to be solved.

If something goes bad over the next few days I will post.

Not MTU
 

Well,

Turns out that it wasn't MTU but instead deleting com.apple.airport.preferences.plist and then rebooting the computer.

I can't even seem to get changes to MTU to persist.

Also when I got onto the wireless at work via the access point that typically causes me a lot of trouble I didn't have any issues. However, when I tried to get on later back in my office I was having DNS timeout issues, pinging the DNS server was timing out, etc.

So... not really sure I discovered anything.

It does bother me though that I can't get MTU changes to stick unless I pick something below 1500.

More Info
 

Well,

It seems the problem has something to do with running a VMWare Fusion virtual machine.

What happens is that over time I seem to lose my ability to talk to our DNS servers from both the virtual machine and the Mac. If I try to ping the DNS servers I will see that ability degrade to the point where I have 100% packet loss.

If I completely exit Fusion, delete com.apple.airport.preferences.plist and power cycle the AirPort I get connectivity back.

I'm not going to run the virtual machine for a couple of days to see if that is the issue.

Note that I did not have an issue with the virtual machine and 10.5.2 so still think this is a bug Apple introduced around 10.5.4.