
Another reason for not responding issue may be frozen internet connection - test it as well.This problem became less common with SSD disks, however, it is a safe move.
You can also try to run a check disk - often the software freezes just because of the disk error - when the process cannot read the data from the hard disk. Check your system with this powerfull specialized utility: IT Sponge. So, here comes a time to do some DYI Windows maitenance: If the process is freezing again and again, it indicates a deeper problem in your system. Start task manager and kill the primopdf.exe in it. However, if the problem persists, you can try this two quick solutions: Modern Windows can often recover and mostly you can simply start primopdf.exe again and continue in your work. This problem is more serious in older versions of Windows, say XP (which you should not use either).
The (un)famous message appears: primopdf.exe is not responding and will be terminated. The typical situation is: you "click on something", Windows appears to be frozen, and after several seconds (or minutes, if you are really lucky :-), What to do if primopdf.exe is not responding A general guide for all versions of Windows, including XP, Vista, Windows7, 8 and Windows 10