A couple of things to try initially.
1. Run a Disk file check process to check for and attempt repair of any disk file format / indexing errors.
- Assuming you are able to login to Windows 10 successfully, Right-Click the Windows start icon (bottom left-hand corner of screen) and select the option "Command Prompt (Admin)" and click 'Yes' to open up a 'Command Prompt' window.
- In the the 'Command Prompt' Window, using the Keyboard, type / enter the following text (exactly as shown including the spaces):-
CHKDSK C: /F
and press the keyboard 'Enter' Key.
- Press and enter the 'Y' key in response to the (Y/N) message.
- Now restart your Computer and a Check Disk operation will commence at Windows Startup. Let it run which may take a while to complete.
- On completion Windows will then startup automatically to the usual Login screen where you can then test to see if the problem is no longer.
2. If option 1 fails, you could try attempting a system point restore operation to return the system to a previous state. Info on how to perform a system restore point, including some other useful troubleshoot info, is avaialable at the following Microsoft web link:-
http://windows.microsoft.com/en-gb/windows-10/windows-10-recovery-options