I just recently purchased a 2TB WD20EARS Hard Drive and It is replacing another Hard Drive that Died. I Plugged it In, Everything seemed to be working fine. I Formatted it NTFS, Added Drive letter E to it (which was the same as the old drive its replacing). Copied all my data over to it and then noticed after every reboot of my computer the Drive will loose the E: Drive Letter. So to sum things up, After every reboot I have to go into Device Manager and Add E: to the hard drive so it shows up under my computer.. It Only does this in my Primary Computer. I plugged it into my HTPC and gave it a drive letter and everything worked fine, even after several reboots. Is it possible there is something in the registry causing the drive letter to be conflicting or something? I am on Windows 7 Ultimate 64bit btw. Any help would be greatly appreciated..