Well, I hate to burst your bubble, but if you're trying to boot off of the old OS, then you might very well be outta luck. I had an HP computer, and pulled the hdd out and installed it in a custom built machine and tried to boot...it gave an error that the version of windows was only for a specific HP computer and wouldn't work on any other machine. Go figure. Also, the partition was locked from the manufacturer, and I had to use a 3rd party program to wipe the drive clean before I could even use the drive.
I was trying to do the same thing that you're trying, and ended up using a different (new) copy of windows and then transferring data via an external USB hdd.
War produces veterans, wounded both physically and mentally. They have sacrificed for us.....and it is now our job to help these veterans, as they have already helped us in ways we will never know, in ways that we cannot fathom, and in ways that we take granted every day.