Use System File Checker (SFC)
Windows 10
To access System File Checker, click here
Scans and verifies the versions of all protected system files. It can also fix issues
The available commands for SFC are as follows
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/scannow - Scans all protected system files immediately (good for fixing issues)
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/scanonce - Scans all protected system files once.
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/scanboot - Scans all protected system files every time the computer is restarted.
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/revert - Returns the scan to its default
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purgecache - Purges the Windows File Protection file cache and scan all protected system files immediately.
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/cachesize=x - Set the size, in MB, of the Windows file protection file cache.
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/? - Displays help as the command prompt.
NOTES:
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You must be logged on as member of the Administrators group to run SFC.
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If SFC discovers that a protected file has been overwritten, it retrieves the correct version of the file from %systemroot% system32\dllcache folder, and then replaces the incorrect file.
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If the %systemroot%\system32\dllcache folder becomes corrupt or unusuable, use sfc /scannow, sfc /scanonce, or sfc /scanboot to repair the contents of the Dllcache directory. (most common one is the /scannow command)
If the SFC does not finish due to errors, you may need to run DSM first and even ChKDSK /r /f command and then the SFC command