I screwed up and locked my HDD and my mobo got fried. Got a 200 gig Maxtor HD that essentially was a paperweight.
Searching the net I found the following website:
http://www.hdd-tools.com/products/rrs/You must make the locked drive the secondary master and disable auto detect in bios, and disable secondary port in Windows XP.
They make a utility to make sure it is locked and if it is you buy an unlock for 49.50.
Took about 15 minutes and low and behold it worked!!!!!!!!
If for some reason it don't, they refund your money.
After doing this, I reformatted on my PC and then put it back into my xbox and it works great (and didn't lock it this time )
As there are continuing problems in their database, this should help if no-one else can access their site.