This window appears usually when the main executable changed or when you set the executable to run as Administrator or your computer is infected with malware.
What is the version of your operating system?
What is the version of your Gig Performer installation?
What is stopping you? 
I opened your attached gig file normally (Windows 11 Pro and Gig Performer 4). Only windows that appeared are ones that stated that backing tracks are missing for rackspaces.