If you're moving it between Mac and Windows, you want to format your flash drive with the FAT32 filesystem. It shouldn't matter whether you format it on your Mac or on a Windows machine.
To do it on the Mac, plug in the flash drive, and open Disk Utility (in your /Applications/Utilities folder). The drive should appear in the list on the left of the DU window.
Select the drive, then click the Erase tab. On that tab, select MS-DOS (FAT) as the volume format, choose a disk name if you want to, then click Erase, and wait.
That said, if your drive just 'didn't work any more' after a while, it may be faulty and it's possible that re-formatting it won't help. (All flash drives do have a finite number of read/write cycles before they don't work reliably any more, too, although it's unlikely you've reached that limit through normal usage.)
To do it on the Mac, plug in the flash drive, and open Disk Utility (in your /Applications/Utilities folder). The drive should appear in the list on the left of the DU window.
Select the drive, then click the Erase tab. On that tab, select MS-DOS (FAT) as the volume format, choose a disk name if you want to, then click Erase, and wait.
That said, if your drive just 'didn't work any more' after a while, it may be faulty and it's possible that re-formatting it won't help. (All flash drives do have a finite number of read/write cycles before they don't work reliably any more, too, although it's unlikely you've reached that limit through normal usage.)
Aug 23, 2008 1:22 PM
Format Flash Drive For Pc
Jon shows you how to (re)format a flash drive for use on both Mac and PC systems. This particular format will allow files bigger than 4 gigabytes! How do I download Mac OS X onto a flash drive on my PC? I have two used Mac Minis without an OS and no DVD player. I need to download a MAC OS onto my PC to a flash drive so I can install it on my Mac Minis. I don't want the MAC OS to try to auto install to my PC and create a huge problem.