The hard drive may not be partitioned. Or may be partitioned in a format windows cannot deal with.
Download this: EASEUS Partition Master 6.1.1 Professional
You will need one writable CD.
Install the program.
Insert blank CD
Goto the start menu > all programs > EASEUS Partition Master 6.1.1 Professional > Bootable Media Builder
Write the program to the disk.
Now shut down the computer, boot from the CD. If the hard disk shows up in the partition tool, then it is functioning properly. select the disk, and delete all partitions, create a new partition, make sure it is a "primary" volume, and NTFS. apply the changes and shut down the computer, boot to the OS now, and check if it is displayed in my computer.
Note: This post was edited by a forum moderator to remove link on 11/28/2011 at 9:05 AM PT
<div><div>My Dell Optiplex GX280 died. I liked it so
well,that i replaced it with the same model and operating system (Windows XP
pro sp3. I took the stuff that I liked out of my dead computer and put it in
the new one (the ram the hard drive and the 2 DVD burners that I had put in
myself.)
Everything if fine except that the new hard drive that I
installed as a backup does not show up. The computer was made to hold two hard
drives. It has the slots and the cables for both drives and a slot to connect
the SATA cable.
Did I miss something? I haven't used two hard
drives before and I'm not sure how it is supposed to work.
</div></div>

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