Airport problem: self assigned IP address?

[neidal]

OK I have a problem which is beginning to annoy me-
setup details:

CISCO Router with IP of 10.75.32.254
D-Link Wireless Access Point with static IP of 10.75.32.24
DNS Server: 202.171.240.58
Wireless network with WEP security enabled called "ABC-MDI" - note password is not HEXADECIMAL or 10 characters.

Small Office of primarily PCs but with about five users with MBP's coming in to the office who need access to the Internet via the CISCO Router

Have no problem connecting via Ethernet Cable plugged right into the MBP (once a unique static IP address has been allocated to that machine in Network Pane) eg. 10.75.32.8

At this stage, the wireless network ABC-MDI does not seem to be doing anything useful like providing internet access as the wired Ethernet is being utilised.

Have tried to connect to the Wireless Network via my iPod Touch, can connect to the ABC-MDI network OK once entering the password, but again no luck in getting internet access. Should I be using the Static IP address of the D-Link Wireless Access Point (10.75.32.24) or another available IP Address (eg. 10.75.32.16)?

Any ideas? It seems like the CISCO Router doesn't like to play nicely with Airports in allocating an IP address to them via a D-Link Wireless Access Point.
Both MBP's are 15" Core 2 Duo's

Many thanks!

[bshirley]

MacBook 2.4GHz, Core 2 Duo
10.5.7
2Wire AT&T - 10 digit password

no problem connecting with iPod Touch
initially connected with MacBooc,
(has slept)

now getting "self-assigned IP" of 169.x.x.x,
"assist me.." to create a new location didn't help
deleting /Library/Preferences/.../...airport... didn't help
auto-reattached to the same 2wire when rebooted

quite annoyed, Apple

[TylerDurden]

Have you tried to reset the DHCP? Click Advanced button the select the TCI/IP tab. Change the DHCP setting to manual then back to DHCP and hit apply.

If this doesn't resolve the issue, try adding a new location and click apply. Please respond with results.

[jjv5]

I have had the same self-assigned IP address problem as many others only when connecting to WPA2 networks.

I have tried all the various "solutions" to no avail. The breadth of solutions that seem to work, but on for a little while, suggests a hardware problem.

I tested airport cards between three Macbook Pro laptops. One card consistently gives self-assigned IP address in any machine it's installed in.

Model A1211, A1226 and A1260

Airport card model: AR5BXB72 - perform flawlessly in any of the above laptops
Airport card model: BCM94321MC - fails with self assigned IP in all three laptops but connections to non-WPA protected networks work just fine.

The aiport cards were swapped between machines, tested, then swapped back and tested again. This process was repeated twice for all laptops and cards and was also repeated in two different geographic locations.

Same result every time.

A quick google search points to a number of problems with the BCM94321MC cards.

If you are having the self-assigned IP address problem check your card type. It shows as Aiport Extreme (0x14E4, 0x8C) in System Profiler, although I'm not sure that's specific enough for the exact model.

If you're having WPA2 problems post your airport card model number.

[katandmouse]

We trashed our airport prefs in Tiger and it worked.

Couldn't find the same file in Leopard, so we searched on "airport" and found something we thought was the same. Trashed it and it worked. Sorry, can't remember the name of the file.

[sqpt]

Same problem

Here is my Wireless Card Type from the system profiler: AirPort Extreme (0x14E4, 0x4E)
Wireless Card Locale: USA
Wireless Card Firmware Version: Broadcom BCM43xx 1.0 (4.170.25.8)
Current Wireless Network: Tako net
Wireless Channel: 1

Since I live in Japan I was wondering if this was an issue of using a netgear wireless router with a Japanese modem, but it appears many folk are having the same issue.

changing my firewall settings did the trick. After connecting to a different secure wireless network from my MacBookPro (10.5.8) I returned home to find that my airport connection had a self-assigned IP and might not be able to connect to the internet.

I had noticed several times before that a message had popped up asking "do you want the application "configd" to accept incoming network connections?" I must have selected no at some point. (or the popup message timed out and selected no automatically) Apparently this configd has control of DHCP and was F-ing up my connection (because I had inadvertently denied it access). I allowed all incoming connections under System Preferences > Security > Firewall, to test and viola! DHCP worked again (after a minute or so) and the internet and I lived happily ever after.

(though you may not want to allow all incoming connections I suppose)

Strange enough that this problem start since 2004 and till now we are still facing it, i am using iMac 20" with OSX10.5.8, same thing after 5 months continuously use the same router suddenly not working, I had tried all the suggestions that i can, nothing works for me except change the router with new router problem gone, but let see how long does it goes.

[theperson10]

Apologies for reviving an old thread, but I believe I can shed some light on the issue.

It turns out that DHCP on an OS X machine - any OS X macine - involves a program called configd (see here for some info on it) This program needs to be able to talk to a DHCP server in order to get a correct IP.
Sometimes, this doesn't happen. On a 10.5.x machine, sometimes the firewall gets configured in such a way as to block incoming data for configd. The result of this is endless trouble and frustration.

On a 10.5 machine, the simplest solution is to reset the firewall to factory defaults as per this page Or, you can use the command line defaults utility to fiddle with it. (advanced users only, please) If you want, you can try using the GUI to add configd, like so:
Go to: System Preferences > Security > Firewall
click the + button.
Press Command-Shift-G to bring up the "go to path" dialog.
type in (without quotes): "/usr/sbin" and press enter.
Select configd, press "Add"

This probably won't really fix the problem, as configd is probably already in the prefs file. It is unknown how the firewall handles duplicates in the prefs file. At least, I don't know.

Trying to figure out the same thing with my AX

[mike]

This old thread ain't finished. G4 powerbook 1.5hz 10.5.8
This started happening to me switching between work and home networks. "AirPort has a self-assigned IP address". Solved by deleting .com.apple.airport.preferences.plist found in the root user folder AND rebooting. Upon reboot the firewall demanded confirmation for "the application" (nothing launched) to accept incomming connections to "mDNSResponder" I accepted. Immediate connection. First attempts to just delete and reconnect didn't work. The reboot solved the problem. This deletion required neither a rebuild of my user network preferences (home and work networks still saved) nor the keychain passwords.

I've read through most of this thread and none of the suggestions either applied to me (those using airport base stations) or use terminology I didn't quite understand (such as the in post above me said to delete a certain file in a root folder...can't find it anywhere).

If my limited understanding is correct, I shouldn't have to have an external router if my iMac as a built in Airport Utility (as in you can have a network setup from the iMac which acts as a wireless router). If that is so, how do I know what ip address/submask/router to enter in?

Now I have had some success getting my network setup, but 4 times in the last year or so it seems my network wants to just disappear hence screwing up everything tied to the network and I'm without a way to effectively and consistently get it back up and running. I am quite behind the times in regards to computer networking. Any help will be appreciated.

Thank you Floridadude! I followed your advice and my problem is solved.

I have an Airport Extreme. My new iMac is connected to it by Airport just fine. So is my iPhone. My 15" Powerbook was also connected by Airport until I decided to use it last night.

I read thru all of the posts and tried a lot of the suggestions. The post by Floridadude (#89) was the only one that worked.

I could not connect using my ethernet DSL cable either. Apparently, my laptop was sitting there in a state of no IP address since Feb 5 (judging by my Mailbox). I think that was when I decided it might be a good idea to let the battery drain... looking back, maybe that's why Mobile Me was acting a little funny as well.

Anyhow, my firewall prefs were set to "Set access for specific services and applications." I changed it to "Allow all incoming connections" and then opened up the Network pref. It worked!

I went back to Security and set it to "Allow only essential services."

I put my laptop to sleep, and after I woke it I was still connected. I restarted, and I was still connected.

I am thrilled! Thank you Floridadude. Now I think I'll go do some software updates

Quote: Originally Posted by Floridadude 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

[Johnsen]

So i read the first few pages of this post because I had the same frustrating issue. I have never used my firewall so I didn't need to go through the appropriate steps for troubleshooting that. The only way I was able to use my Netgear router was to manually punch in the appropriate info in the advanced Airport settings. I was able to solve my "Static IP address" issue by doing the following...

- Open up "Keychain Access" (spotlighting it is easiest)
- On the left side towards the bottom, under "Category" select "Passwords"
- Find your login info in the list provided
- Double-tap on your login info and select the "Access Control" tab
- Enter your password if asked
- Finally, make sure it is set to "Allow all applications to access this item"
- Hit "Save Changes"

This worked for me without the need to trash my AirportPreference.plist (whatever the full name of it is)

I don't know how this got set this way on my MacBook Pro but this thankfully solved my problem!

Hopefully this will prove successful for you too. Let me know if it does not.

P.S I'm running a Late 2009 13" MacBook Pro 2.26 GHz with Snowleopard 10.6.3

Hi, I'm new to this forum but have read the posts in this thread with equal interest and disappointment as there is no clear resolution to the problem of self-assigned IP numbers.

In my case I am using an iMac G4 running OS X 10.4. I had no airport card but did have a spare Belkin F5D6050 (ver. 100 it says) and downloaded the OS X driver from the belkin website. It worked fine for perhaps a couple of months, then became very temperamental.

It is the same problem reported here. A good wireless connection to the router, but a self-assigned IP number meant that it would not browse the internet. Is there no way to get out of this trap?

[mrblueslee]

Thank you Johnsen. I've been having the Self-Assigned IP Address problem and I did what you suggested and it worked like a charm!

Just to summarize the solution:
1) Open up "Keychain Access" (spotlighting it is easiest)
2) Bottom-left under "Category" select "Passwords"
3) Find your wifi network (listed alphabetically) and double click it
4) Select the "Access Control" tab
5) Make sure it is set to "Allow all applications to access this item"
6) Click "Save Changes"

I'm on a 15" MacBook Pro 2.2 GHz Intel Core 2 Duo w/ Leopard 10.5.8

[moulton06]

I had some problems with accessing the internet using the air-port facility on the mac book pro. just want to share with you a few thing that i tried, both what worked and what didn't

Reset the router - didn't work
put in the IP address manually - didn't work
system restore and repair - didn't work
up date Mac OS - didn't work

used an ethernet cable into the router - worked
disable the WEP Key - worked
re-enabled the WEP Key - worked

when I disable and re-enabled the WEP Key the Air Port the found the IP address and now working fine.

Hope this Helps

I've been having the "self assigned ip" problem for ages...and I think I found the EASIEST SOLUTION !

1st Step

Go to "Open Network Preferences"
then click on "Advanced"
then click on the submenu "Airport"

Now ERASE all your SAVED NETWORKS clicking the minus botton (-)

2nd Step:

Open the application "Keychain Access"
ERASE all your SAVED PASSWORDS of your wifi networks

Now once you have erased evrything that had to do with the "BAD networks"
RESTART your Mac

And the problem is gone !! i hope it works for you too !

good luck !

[sean.peters]

My wife was having this problem on her older Powerbook G4 (running 10.5.x) - as usual, it happened after the battery ran down. Deleting the .plist had no effect. The solution that worked for me was to toggle the firewall to "allow all..." - at which point the DHCP service started working - and back to "set access...".

That's all fine and dandy, but I actually had a question about one of the other proposed solutions: getting into Keychain Access and diddling around with which applications can use the airport password. I'm a little nervous about opening that up to just absolutely any process - if your machine got infected, wouldn't you be opening up your entire network to it? If anyone understands the security implications of doing this, I'd be grateful to hear them (as the wife's machine was and is set to only let certain processes use the network).

[Ricard]

I am sharing my experience of this problem (now solved) with my Macbook Pro OSX 10.6.4 in the hope it may help others.

My wireless network connection had worked fine at home until I went away and connected at a hotel one weekend. After this, it could not connect to the internet over wireless and Airport reported "self assigned IP address". No problem when using ethernet cable, Firewall was turned off.

Tried everything on this thread without success, took Macbook to Genius Bar, wireless worked immediately on their network. They didn't suggest that this meant there wasn't a problem, but deleted the network and airport preference files at Library/Preferences/System Configuration, tested my hardware and suggested I use Automatic Location rather than Home.

They also claimed to have deleted the Home location and my home network which was called Study.

Unfortunately when I got home this had not helped and the problem remained unchanged. Notably when the Macbook scanned for networks and found "Study" as well as various neighbours networks, it identified "Study" as a known network, so the Genius Bar guy obviously had not succeded in removing the Macbooks memory of this network.

I then tried to approach the matter from the other end. As everything had immediately worked on a new unknown network at the Apple Shop, I changed my router's wireless settings to give it a new name "NewStudy", I set it to a different frequency channel and I changed the password so that it would look like a completely different Network.

My Macbook now immediately connected to "NewStudy" (once I had put the password in) with no problem. I therefore concluded that the Mac keeps some knowledge of wireless networks in a place that is well hidden (the Apple Store Genius apparently didn't know of it) and if you somehow manage to screw up the settings relating to that network it seems nigh on impossible to get rid of it and start again.

Now the interesting part. Before I set about the task of changing all the network settings in several other wireless devices in the house that had been working perfectly well on "Study", I tried putting all the router settings back where they started. Lo and behold my Macbook again worked perfectly having discovered "Study" and been given the password (which was back to the original one).

This makes me think that perhaps the Macbook identifies a network by some other factor than the ones I had been able to change (MAC address maybe). So when I changed the name, password and frequency of the wireless network, it realised it was the same device, but finding a new name etc. ditched its previous settings and started again which is of course what I wanted it to do.

If anybody actually knows how this works and can provide some theoretical explanation for this rather than my deduction from empirical evidence, I would be most interested.

On a more practical note I would suggest anybody stuck with this problem, try changing the settings on your wireless router to something else, connect to it and then change everything back again if other people or things use the network. Good Luck!