I installed a copy of Vista Ultimate that had been an XP box a couple of years ago and it has been humming along happy as a clam ever since. Recently I caught a virus and thought that I would just install another instance of Vista on a different drive on the same machine and just migrate my applications over time. This is my photo editing machine so it is really important to my business. In the process of trying to install Vista it wouldn't recognize my SATA drives and long story short I had to reformat the IDE drive that Vista was previously installed on and install it there. Of course I had done backups to my external drives so I didn't lose any data but. For this installation, because I no longer have the XP disk (moved three times) I installed without entering the serial number thinking I would find the old disk which I can't. How can I get this copy activated again?