Recently, I encountered a unique problem - After installing WPS Office 2016 on Windows 10, Edge browser failed to open PDF file and instead when ever I double clicked any PDF file it would ask 'Do yo want to open ....' and after clicking open it would show a blank page and the file in the downloading tab. Although Edge was the default App for opening PDF file and I even re-selected it - but it didn't help. Solution: After much fiddling I found that you need to go to All apps > WPS Office > WPS Configuration Tools and select "Advanced..." and uncheck the box Portable Document Format (*.pdf) May be of help !
You have to specify the default program to open .pdf files, then will not ask more. And if after the restart still asks, is your Windows is corrupted. (Error does not make sense to look for, so or so you will not find it, try to find reason and then make a new Windows installation). WPS is certainly not the reason , of course, if you do not use any strange (weird) crack, patch or repack versions.
Seems you have not read my post properly - I already tried this. Windows is not corrupted since I was able to replicate the error on another system. I don't use pirated software's - it was WPS Office 2016 personal (Free) version 10.1.0.5507 (latest). And I posted here to help others in case they encounter similar problem - Solution is also provided FYI.
I have a feeling that Windows 10 is half-cooked. I have been using Windows 10 for 4 months and have met several problems. Although they are not serious problem but I decided to postpone from upgrading my other PCs to Windows 10.