You didn't specifically mention which operating system you're using but your mention of "File Explorer" makes it appear like Windows 10. As such, it seems as though the Windows 10 "upgrade" process may not install all the files correctly, or maybe they're damaged, or maybe something else, but running Chkdsk has fixed quite a few of these minor glitches. Try running Chkdsk in "repair" mode to find any damaged files and correct them. Start by opening a command prompt as an admin. RIGHT click on the Start button, choose "Command Prompt (Admin). Once there, type chkdsk /f /r /x, leaving the appropriate spaces between the letters as shown, then press the Enter key. You should see a note that it can't be run till a restart is done, type "Y" for yes, then press the Enter key again. Close the command prompt and restart the computer. Chkdsk will run upon restart and will take quite a while to finish.. Don't panic when the progress bar stays at 10% for a long time. It's fairly normal and the Chkdsk process may take a couple of hours.
When it's finished, it will boot to your normal startup/lock screen and you can login normally and then see if things are working correctly again.
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If that doesn't get it done, then try scanning for malware using the instructions in the link below. Follow the instructions to the letter. The scanning tools will search for more things than your standard antivirus program.
“Expand” the post titled: "Please try this" at the link below:
http://www.cnet.com/forums/post/f742c795-5881-433b-a29b-6d758efe5cd3/
Hope this helps.
Grif
Hello. My computer crashing every time I right click on any file or folder in File Explorer. It closes on its own and I have to re-open it but I can't right click on this. This is really annoying and never used to happen. Any reasons and how I can stop it? Thanks.

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