sounds like it may have worked a lead loose. open the case and check its connected.
if it is (both leads I/0 and power) then you may have a hardware compatibility issue.
is win7 an recent upgrade from xp?
Windows 7 my computer shows disks my two partitions device manager and disk management do not show my hard drive
Just checking - Windows 7 is working but you can't see your hard disk? Are these two Partitions on a different disk from the one you're looking for? If W7 won't load, can you tap whichever key gets you into BIOS to see if the disk is show in there?