This appears to be some weird software problem. First, run an antivirus scan on your computer. If you don't pay for one, there is a fine one built into Windows called Windows Security. Open up the program, select Virus & threat protection from the sidebar, click scan options, select the full scan radio button and click Scan Now. It'll take about half an hour to run, depending on how many files you have. If the scan says there were no threats, then I would just reinstall Windows. Open Settings, click updates and security and choose the recovery tab. From there, click the Get Started button under Reset this PC. There are options to both keep and delete all your files while Windows is reinstalling. I would do the keep files option, but make sure you create a complete backup to an external drive or the cloud in case something goes wrong during the reinstall. Click through all the dialogue and eventually Windows will start reinstalling. This can take anywhere from a half hour to several hours, depending on the speed of your computer and hard drive. Once it finishes, you may have to run through setup but all your files should (notice I say should, not will) be there. If something went wrong, just restore from your backup.
Good luck!