TA error code 27Solved

What does the TurboActivate error code 27 mean?The message says: "You must enter a valid product key."But I just generated a brand new key, and I'm getting this error.

Does the key from the previous version have to be deleted before the key for a newer version will work?

I just ran my program EXE (without running the installer) and I was able to activate the key successfully. So, the error has to do with something in the Inno Setup file.

I found the problem. My Inno Setup file was missing some code. Got the missing code from the API / Installers / Inno Setup sampel file. Now things are working OK.