As this might be related to malware (though not sure) I would do this:
1) download 
Malwarebytes from 
here and 
CCleaner form 
Link Removed and save them on a USB flash drive
2) restart computer in 
Safe Mode without network (press 
F8 once the computer restarts)
3) run 
Disk Cleanup utility to remove the files that are not needed anymore (not your personal files)
4) uninstall or disable your antivirus (so that it does not conflict with Malwarebytes)
5) install 
Malwarebytes and let it scan your computer
6) remove/uninstall Malwarebytes and reinstall/enable your antivirus
7) run 
CCleaner to fix the registry
8) restart your computer in normal mode
Let us know if the problem is solved!