How to format U3 USB drive on a Mac // Jan 13, 10:19 PM

I’m hoping the title of this post is explicit enough for a Google bot to cache and save somebody the time I spent looking for a way to format a USB drive like the one I got for Christmas. If you’re just looking for a quick way to format the drive and don’t care about my interlude, skip ahead to the instructions.

U3 “Smart” drives are USB drives which ship with Firefox, Thunderbird and some other applications pre-installed. Upon plugging in the drive, aside from the regular USB-device-attached icon, there appears another icon in the system tray which mimics your regular Microsoft Windows “Start” button, only difference being that you get your U3 drive applications and documents.

For some people, this may have some utility, but the problem is that if you’re just looking for a plain old USB drive, pre-installed software takes up your valuable space, and that if you are using a Mac, the whole thing is useless. U3 drives ships partitioned into 2 volumes, one of which contains the “smart” software, the other one your data. The storage volume appears as your regular USB drive while the partition containing the software mounts as a read-only disc on your desktop.

Looking to uninstall the thing by formatting the drive, I first opened Disk Utility application only to realize that while I can format the storage volume, Disk Utility doesn’t offer any means of formatting the read-only partition.

Googling around I found the removal instructions and downloaded the uninstaller executable for Windows. If you’re taking this route, beware that SanDisk devices have separate uninstaller (the former instructions apply to all other manufacturers). Luckily, I do use Parallels to run Windows on my Mac. It would have been great if it had worked but it didn’t. After getting the same “unable to perform the operation” error several times when running the uninstaller under Windows, it was time to venture into the UNIX command line. While Disk Utility application won’t prove helpful in this situation, manual page of “Diskutil” command will tell you all you need to know.

To conclude, if you’re using a Mac and have absolutely no need for U3 software on your USB drive: Open Terminal application and type

Diskutil list

That should give you the list of currently available disks. Find your USB drive on the list. Name of mine was disk1.

Type

Diskutil eraseDisk MS-DOS "My New USB Drive" disk1

(Make sure to replace disk1 with appropriate value.)

This will format your drive (and naturally erase all data on it) with FAT-32 filesystem and with the name of “My New USB Drive”. If you’re never going to use your USB drive on anything other than the Mac, feel free to use “HFS+” instead of “MS-DOS”. The latter will give you the greatest compatibility though, and at the same time impose restrictions of that filesystem (like inability to have your drive titled “John’s Drive” with an apostrophe).

Update: Some people have reported that the above instructions don’t work for them. I hope they work for you and of course I can’t possibly guarantee it will work for everybody. If you get an error related to permissions after running Diskutil, try typing sudo before the Diskutil command.

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