Pirform is licensed to the computer. If your licence expires then you can open Pirform in "safe mode".
This mode allows you to keep on accessing your certificates as PDF files, take a backup of your certificates and use the easy access menu to get to your data folders. But it will not allow you to add or change any certificates.
If you want to reenter a licence, you can do that by opening Pirform Options.
Pirform warns you that it is running in "safe mode" when it starts: