This can also happen when a drive is not assigned a Drive letter. If you are just checking to see if the drive shows up in windows, this will often not work.
Check to see if the drive shows up in the BIOS. You should see the drive listed in the BIOS as a drive.
If that shows up, then when you boot into windows you need to do something to attach the drive to a drive letter, I am spacing currently how to do this. But there is certainly a decent tutorial on the web on how to do this. From what I remember, it was somewhere in the Drive management section of windows (imagine thats where something like that would be)
Good Luck