I am experiencing some weird problem with my HITACHI 40G external USB HDD (FAT32)...It has been working for 2 years no problems on both Mac and PC. Haven't used it for 4 weeks as I sent my macbook to repair due to the random shut down problem. Now the device starts but it doesn't show up as a external device, i.e. I don't have access.

Is it because of the new Software Update?

Funny thing is I have 3 hard drives (External all using USB connection, 2x 3.5"desktop drive, and 1x 2.5" laptop drive, all formatted as FAT32) The 2 desktop drives work perfectly on my mac book pro however only the 2.5" HITACHI HDD does not work anymore. The light on the HDD was on when I plug it in and I can hear it running but just my lovely OS X does not wanna show it as a device in either Macintosh HD, desktop or disk utility.

I still can't figure out why, because:
- The two 3.5" ext. HDD work on my macbook pro, so it is not usb port problem as such.
- The 2.5" ext HDD works on my colleague's macbook pro and my work pc (win xp), so it is not the ext. hard drive problem either!!

I am confused, I am lost........

What problem could it be????????????? It will be great if someone have any ideas of what weird thing is going on... Thanks Millions