kirriejim, XSKey is the Emagic Logic Platinum copy protection key click here. What I think has happened is that you have restored your system to a fresh installation of Emagic Logic Platinum, but the date on your pc is saying that the trial period has expired, and you don't have a valid XSKEY for your installation. I suggest an e-mail to EMAGIC may be needed to resolve your problem. click here
I did find a reference to "XSKEY not found", but it was in Russian click here.