USB Harddrive Problem

I'm about to pull out what very little hair I have, I hope some one can help me!

I put together a USB powered external laptop harddrive- HD-

in this external case-

I'm using XP Pro SP2. P4 2.8 on a Asus P4PE with 512MB Memory. "C" drive is a WD 120Gb SATA, slave is a WD 80Gb SATA. The HD does spin and the lights come on so it is getting power. I can't get the darn USB 2 HD to show up in "My Computer" so I can use the thing. and shows a location on "O" and that it is working properly. However it DOES NOT show up under "Disk Manager" anywhere nor in "My Computer" I installed the HD itself in my daughter laptop (I pulled her HD out) and I formatted and installed XP just to see if it was the HD at fault. The HD worked perfectly. I disconnected all the HD's from my computer and tried to boot off of the laptop HD connected to all 12 USB 2 ports I have, but it will not boot off of a USB drive. It does show up under DOS when in setup mode and shows the correct size of the HD. If tried "F-Disk" but it says it does not work under "XP", I have PowerQuest ParbreastionMagic 8.0 but it does not work right because I have a HP printer and scanner (If had this go a round before and both PQ and HP tech support both said it was a problem with the HP printer) I just want to use the thing as a back up drive to move files back and forth.

This is my second external enclosure (same model) the first one did not work at all. NewEgg took it back with now problems at all-a GREAT company to do business with by the way....

So is the second enclosure bad too or WTF am I doing wrong here?????

TIA, Klumze