I can't find the external hard disk in "My computer"

This is Windows XP Media Center Edition 2005. System is working fine so far. Recently I bought a new HITACHI 2.5'' external hard disk and have used it on few computers, its working fine. But when am connecting it to this computer, I can see it as “USB mass storage device” in safely remove hardware icon but it is not visible in My Computers.

Before I post the problem here I again checked it in my laptop and its still working good. So what could be the problem with my system? Any help or idea? Thank you in advance.

Hi ChisholM, yoiu should check out these existing discussions describing the same problem, Hope you get some help:
http://forums.techarena.in/mediacenter/812994.htm
http://forums.techarena.in/hardware-...ls/1390225.htm