Lost Product Code (Key) for Web Design Software

I upgraded from Web Design 6 to the WD Premium software online last year. Recently, I had to reload Windows and programs onto my pc after pc issues. I moved my programs over to an external backup drive but now, when reloading it to my pc, it's asking for the product code to register the software and will only let me use the program as a trial for a few weeks without it. I'm unable to find the email with that information. Can anyone give me some ideas as to a solution to this?

Thank you,