Try these first to see if they work:
Open Start, type: CMD
Right click CMD
Click Run as administrator
Type in at the prompt OR Copy and Paste these one at a time : (Hit enter after each)
Dism /Online /Cleanup-Image /CheckHealth
Dism /Online /Cleanup-Image /ScanHealth
Dism /Online /Cleanup-Image /RestoreHealth
Also run the System File Checker utility:
Open Start, type: CMD
Right click CMD
Click Run as administrator
At the Command Prompt, type: sfc/scannow
This will check for any integrity violations
Restart your system
If that does not work, try performing a repair upgrade:
http://answers.microsoft.com/en-us/insider/wiki...
Could you confirm if this also happens in the default Administrator account?
Open Start
Type: cmd
Right click CMD
Click Run as administrator
At the command prompt, type:
net user administrator/active:yes
Hit Enter
Close command prompt, restart, then try signing into the Administrator account.
Try launching File Explorer again.
Which Antivirus utility do you have installed?