For persistent issues where a valid code is rejected, contact NCH Software directly rather than using unofficial "fixes": Technical Support PhotoStage Slideshow Producer
Compare the mentioned above.
You will still have the watermark on export, but the annoying popups will stop. photostage slideshow producer registration code free fix
If you have your valid registration code and want to apply it: Open PhotoStage Slideshow Producer. From the top-left corner, click the From the dropdown list, select For persistent issues where a valid code is
: If you have a 12- or 13-digit serial number , it is not the registration code. You must first activate it at the NCH Activation Page to receive your final registration and activation code. From the top-left corner, click the From the
When you launch Photostage Slideshow Producer, you might see a prompt asking for a registration code. This can be frustrating, especially if you've already purchased the software or simply want to try it out. The good news is that there's a way to bypass this registration code requirement.