Thread: Usb not recognized

I'm running Vista, but this problem also happened with XP. At the class, when I connect my external USB hard drive, it shows in Windows Explorer as drive E: and all is well. At the class I also connect to drive F: on our server and drive U: on a different machine.
At home, the external drive does not always shows in Windows Explorer and so it is not accessible.
If I disconnect the drive from its USB port and connect it back into the same port. But if I connect it into a different USB port then the drive finally appears. What is issue is this, and why does not the drive always connect at home as E: as it does in the class?

The reason for this issue is that there is one more device which takes sometimes more than the preferred drive letter. If this is the case, should not change the drive letter to one more device or use a drive letter other than E: to external drive. But if there is no external device, you can tell Vista that you are always E: Here is the procedure for determining exact drive letter.

Click Start and enter diskmgmt.msc ball to start the Disk Management program. Right-click the external drives and selects Change drive letter and paths from the popup menu. Click Remove, and confirm the worry-warts command that says some programs may not function properly. Right-click again and choose Change drive letter and paths. Click Add and add E: drive letter. Close Disk Management. The movement should now appear as E: each time.

thanxs for suggestion.........