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!