Ok, more details time...
I put some music on it and gave it to the flatmate.

Now when I plug it in the drivers think the pendrive is working, the USB port is working. However, every time I try to access it, it prompts me to format it. Which doesn't work.

In the properties menu it says:
Type: Removable disk
File system: RAW
Used space: 0 bytes
Free space: 0 bytes
Capacity: 0 bytes

EDIT - Ah well, will try other things. Mainly getting him to replace the bloody thing!
(Meya, Tue 27 Oct 2009, 18:07, 1 reply, 16 years ago)

OK, it sounds like the hardware is OK and it has just got its knickers in a twist
Right Click on the My Computer icon and choose "Manage" then click "Disk Management" on the left hand side.

This should show you a list of the drives in the computer on the right.

VERY CAREFULLY find the drive letter of the broken USB key and delete any existing partitions, I'll say again VERY CAREFULLY as if you delete the wrong thing here things get messy quickly.

Now right click on the empty drive and create a new FAT32 partition. hopefully this will get you back to a blank usable drive.
(bill, Tue 27 Oct 2009, 18:26, Reply)

According to the Computer Management screen the layout is partitioned but there is no way to delete said partition. It also won't let me make a new partition from that screen.
(Meya, Tue 27 Oct 2009, 18:42, Reply)

That I hadn't realised
you might want to try this:
www.ghacks.net/2009/04/17/partition-usb-flash-drives/

Which describes a program that might help:
files.filefront.com/lexar+usb+formatzip/;10112841;/fileinfo.html
(bill, Tue 27 Oct 2009, 21:52, Reply)