Alright, I'm not actually sure if Xboxhdm damaged my retail Xbox HD but it was locked and I unlocked it with HDDUnlock. Then, I downloaded Xboxhdm and followed the instructions to a T. When I was prompted to install a C drive, I accepted and the C drive was successfully formatted and installed (thanks to Slayer's).
However, when it next prompted me to do the same for the E drive, I accepted and my computer more or less locked up. Nevertheless, I left my computer alone for half an hour or so and when I came back I was at the title menu for Xboxhdm (where you pick what you want to do to your HD [e.g. clone, full format and install, etc]).
So, I popped in the floppy that Xboxhdm created, rebooted, and went to lock my HD. Now, I ran Hdlock and set my Xbox password as XBOX and popped the HD out of my computer. Unfortunately, my Xbox still gave me error 6 so I popped it in thinking that I might have had some trouble come from when formatting my E drive locked up my computer.
Here's the kicker: My hd thinks it's locked and won't accept the password XBOX. I made damn sure that the PW was XBOX but the log saved on my floppy drive under A:\logs\hddpw.txt was blank where it should have shown my logged PW. Regardless, I still locked the HD with XBOX.
To make things stranger, while frigging around with stuff, I ran all of the utilities provided on the floppy and on the Xboxhdm disk and was able to eventually lock and then unlock the HD with the password BLOG. After that, I ran ATAPWD which, previous to the PW "change" hadn't accepted any changes, allowed me to unlock (or so it said) my Xboxhd. Giddy as a schoolgirl, I ran the CD to do a full format and install with Xboxhdm only to find that it thinks my HD is still locked.
Now neither password will lock or unlock my HD under any utility. However, if I do run any of the lock/unlock utilities on the floppy and put random letters or just leaving the PW request field blank it says my HD is respectively locked or unlocked.
Naturally, ATAPWD and the Xboxhdm format tool say my HD is locked.
What the fux0rz?