Thanks trevor :) I'll let you know how things go :)

Cheers,


David

The software on the stick was successfully uninstalled via the XP PC, and the stick has been reformatted to MacOS Extended.

SUCCESS! :D

The only puzzling thing is that there's only 3.69GB of space on a 4GB stick ... seems quite a lot of stuff to be used up? Can I somehow erase it *further*?

Many thanks,


David :)

4,000,000,000/1024/1024/1024=3.7252903GB

Overhead (Directories/Partitioning) is using about 30MB. You might be able to squeeze a bit more out of it if you partition using Apple Partition Map rather than GUID.

Hard/flash drive companies use some dumb numbering system to count the amount of space on the drive, most likely just to make the drive seem larger than it actually is. Somewhat like how people sell things for $9.95 instead of $10, except this is in reverse.

The drive companies use multiples of 10 (10,20,30,...1000)to calculate disk space, while the computer uses multiples of 8 (8,16,32,64,...1024). There's obviously a difference in counting disk space this way.

Back in the days of small 100MB hard drives, this didn't really matter much, as the calculations were only off by about 4 MB of space.

Today, this difference is much greater, because the capacity of the drives are much larger. A 200GB HD is actually only about 187 GB!

To the company, a 200GB HD is 200000000000 bytes (200*1000*1000*1000). 200GB to a computer is 214748364800 bytes (200*1024*1024*1024). So there's a difference of ...214748364800-200000000000=14748364800 bytes= ~13.37 GB.

Ah right, thanks. I knew there was a difference due to the different methods of counting but didn't realise it would be so much.

Thanks again for the explanations :)


David

Actually, computers calculate based on Base2 (1, 2 ,4 ,8 ,16 ,32 ,64 , etc.) or Binary where drive manufacturers use Base10 (1, 10, 100, etc.) or Decimal. Same results though.

The difference with a 200GB drive would be calculated in reverse.

Decimal = 200,000,000,000 / 1000 / 1000 / 1000 = 200 GB
Binary = 200,000,000,000 / 1024 / 1024 / 1024 = 186.264515 GB

A apparent difference of 13.735485 GB.

After U3 uninstall, my Sandisk 8 GB turned into a 4 GB
 

Hello all,

Has anyone (besides me) had an 8 GB device turn into a 4 GB device, by simply uninstalling U3? I'd sure like to get it back to its intended capacity. I have a Sandisk Cruzer 8 GB.

Any assistance would be much appreciated!

- Dan -

Hi there :)

The stick has been performing well on my Mac, but I now find that it's incompatible for use on Windows computers. I formatted it as 'MacOS Extended'. What format do I need to select if I want it compatible across all platforms? Journaled? MS-DOS?

Many thanks for your help :)


David

I believe FAT32 is the format for windows. There are some limitations to it, but it will be cross platform. One limitation of which I'm aware is its inability to copy files larger than 4GB in one go. I have an external hard drive which I formatted as FAT32 to be cross platform with our windows boxes, and couldn't copy dmg files which were slightly greater than 4GB in size. The drive would allow me to create dmg's on it of that size, as the files were created incrementally. I just couldn't drag/copy the big ones.

John is correct. If you need to use this flash drive regularly with many Windows systems, then format it as FAT32 or FAT16. Note that Disk Utility calls FAT filesystems "MS-DOS Format", and will choose FAT16 or FAT32 as most appropriate for the size of your USB flash drive.

FAT32 is an old and decrepit file system with some serious limitations. It is also rather delicate. Only format the drive FAT if you need to use this with a lot of Windows computers. If you only need to use it with a single known Windows computer, there are better options such as using MacDrive on the Windows computer to allow it to read HFS+.

Trevor

Many thanks for your help guys, I will try the MS-DOS format and let you know how I get on.


David :)

Two years on, this thread is still the first hit that shows up in google.

Fortunately things have slightly improved in that you can use some sandisk software natively on osx to get rid of the read only partition.

See forum article
http://communities.sandisk.com/sandi...thread.id=1066

which refers to software available at
http://mp3support.sandisk.com/downlo...-utilities.zip

The software seems to be of a beta quality - I noticed some general instability problems with my laptop after installing the software and then running the partition remover, but perhaps that's just coincidence. I checked that the supplied sandisk utility uninstaller removed everything (including kexts) based upon a snap shot taken before the install, and indeed it does. I used the software to get rid of the U3 device and then "uninstalled the uninstaller" and my laptop hasn't missed a beat since I removed the software.

Anyway, the removal of the ghost device on U3 usb keys worked well, freeing up about 150MB on a 4G key. The sandisk software took a copy of the key (keep in mind you'll need enough free space on your root disk for this) and then wrote it back after updating the firmware.

As the capacity of the device increased, the secondary GUID table on the usb key was no longer in the correct location which needs to be corrected. Most things work with just the primary label being correct, but if you want to modify the layout, you'll need to rectify the inconsistency. To do that use disk utility to unmount the filesystems on the key (don't use eject). Use command (apple) 'I' to find out the disk number of the flash key while you are using disk utility.

Then from a terminal run
gpt recover /dev/diskN
where N is the disk number obtained from disk utility info.

Hope this makes sense to anyone still running into the problem.

Cheers.

There is now a Mac Removal Tool

Thread:
http://communities.sandisk.com/sandi...thread.id=1066

Direct Link to Mac Removal Tool:
http://mp3support.sandisk.com/downlo...tility-mac.dmg

Thanks for this information. I was pulling my hair out in frustration over this.

It's baffling that SanDisk has continued shipping U3 after all these years and all these complaints.

Success with the Mac-specific U3 uninstaller!
 

Hi there - i know this is an old post, but i'm registering specifically to post my experience
& give Thanks for finding a solution to this challenge -

please allow me to be heard also, as it will likely help someone else like me in the future -

i googled "remove the u3 cd" and wound up here,
finally getting to post #33 by JAA, who interestingly only has that 1 post,
but it turned out to be the post that helped me, so THANKS JAA wherever/whoever you are!

i was unsuccessful at uninstalling or rewriting the cd-rom component of 3 SanDisk 4GB cruzers
on any of my WinTel boxes,

since sometime in the past i had click-deleted some files on the usb stick -
such that a U3 icon no longer showed up in the system tray
to allow the simple built-in click-uninstaller to work,
nor did it allow the downloaded official removal tool to work,
nor was i successful using Gparted live CD, as Gparted did NOT recognize the CD-rom.

then i dL the Mac uninstaller utility JAA linked in their post,
followed the directions installing & running it on one of my Macs,
& VOILA! worked a charm for all 3 sticks.

then, wonder of wonders, using its built-in uninstaller, cleanly removed it from the iMac :D

Best of luck to all ~

By the way, the Mac removal utility doesn't work under OS 10.6. Needs to be 10.5 or lower.

Neodymium Protocol
 

I too, could not format a sandisk thumb. i read this thread and nearly gave up, until i grabbed the neodymium magnet from my child's lenz law experiment and waived it around the drive.

worked like a charm.

Sorry about your luck. A strong magnetic field can't possibly resuscitate a USB flash drive - which doesn't use any type of magnetic technology.

By the way there is a better Universal Format called EXFAT. This will allow for files sizes greater then 4GB cross platform. Works out of the box with OSX, Vista, Win7. XP/Server 2003 requires a patch http://support.microsoft.com/kb/955704 then it works great there too.

I use this to move Virtual box Vms between windows and mac. Same one works on both. Thing is its currently around 12GB so Exfat was the way to go. I dinked around with ntfs but since its not supported natively on the mac and I wanted to find a clean free solution I found exfat.

EXFAT. Good to know. Thanks anthlover.