At some stage in your computers life It may be necessary to run the System File Checker tool (SFC.exe). Run the System File Checker tool (SFC.exe) Open an elevated command prompt. Win7: Click Start >> All Programs >> Accessories, Now right-click Command Prompt, and then click Run as administrator. If you are prompted for an administrator password or for a confirmation, type the password, or click Allow. Win8 / Win10: Right click on the Start button and select Command Prompt (Admin ) from the quick view menu. In the elevated command prompt, type: sfc /scannow Make sure that you include a space between the c and / and press the Enter key on the keyboard The sfc /scannow command will scan all protected system files, and replace corrupted files with a cached copy that is located in a compressed folder at %WinDir%\System32\dllcache. The %WinDir% placeholder represents the Windows operating system folder. For example, C:\Windows. Note Do not close this Command Prompt window until the verification is 100% complete. The scan results will be shown after this process is finished. After the process is finished, you may receive one of the following messages: Windows Resource Protection did not find any integrity violations. This means that you do not have any missing or corrupted system files. Windows Resource Protection could not perform the requested operation. To resolve this problem, perform the System File Checker scan in safe mode, and make sure that the PendingDeletes and PendingRenames folders exist under %WinDir%\WinSxS\Temp. Windows Resource Protection found corrupt files and successfully repaired them. Details are included in the CBS.Log %WinDir%\Logs\CBS\CBS.log. Windows Resource Protection found corrupt files but was unable to fix some of them. Details are included in the CBS.Log %WinDir%\Logs\CBS\CBS.log. . To view the details that are included in the CBS.Log file, you can copy the information to a Sfcdetails.txt file by using the Findstr command, and then view the details in the Sfcdetails.txt. To do this: Open an elevated command prompt, type: findstr /c:"[SR]" %windir%\logs\cbs\cbs.log >%userprofile%\Desktop\sfcdetails.txt and press the Enter key on the keyboard Click on the sfcdetails.txt file that was just placed on your desktop to see the SFC scan details (ones with the [SR] tags) in the CBS.LOG.