I have a 500GB Transcend USB external hard drive.
I wanted to format it in FAT32 so my MacBook Pro running Snow Leopard could see it as well as my PC. When I went to format the hard drive on my Win7 machine it only gave me NTFS or EX-FAT as options. I formatted in EX-FAT.
No probs, my PC still saw the hard drive
I then connected the external harddrive to the MacBook which picked it up straight away. I wanted to backup the Mac so I copied the entire Mac HDD onto the hard drive, then went and ran Time Capsule on the Mac pointing to the external hard drive.
Finished, I ejected the hard drive and went and plugged it back into my PC. I wanted to transfer the backups I made to an internal hard drive.
The drive is not being detected now. It shows up in 'Device and Printers' but not as a drive in explorer.