I've already deactivated, removed Nitro Pro 10, all folders in appdata, reinstalled and re-activated, still the program crashes. After that, all that was left for me was to put on my mud shoes and go into the windows registry and start deleting everything NitroPDF related. Hours go by and finally I've cleared the registry of all the NitroPDF settings. Now I've reinstalled it again and voila the program works again.
So what did we learn from this?
We still have no idea why this was caused!
So I'd like to say no thank you to the developers and the support of NitroPDF since in the whole month of time I didn't receive a simple tip or a direction where to go or how to solve my problem.
Best regards,
Piskr