system files

Check for corrupted Windows system files

• System File Checker (SFC) is a utility in Windows that scans for corrupted Windows system files. If it finds a problem, it will try to replace the problematic system files from a cached version that’s on your PC. If SFC can’t replace the files, the Deployment Image Service and Management Tool (DISM) can check the corrupted files then download and replace the files through Windows Update.

To run System File Checker (SFC)

• In the search box on the taskbar, type command prompt, press and hold (or right-click) Command Prompt, then select Run as administrator > Yes.
• At the command prompt, type sfc /scannow (note the space between "sfc" and the "/").
• Do one of the following, depending on the results of the scan:
• If SFC finds corrupted files and replaces them, restart your PC and see if that improves your PC’s performance.
• If SFC doesn’t find corrupted files or finds corrupted files but can’t replace them, try using the Deployment Image Service and Management Tool (DISM).

For more info about System File Checker, see 

Use the System File Checker tool to repair missing or corrupted system files.

To use the Deployment Image Service and Management Tool (DISM)

• In the search box on the taskbar, type command prompt, press and hold (or right-click) Command Prompt, and then select Run as administrator > Yes.
• At the command prompt, type dism.exe /Online /Cleanup-image /Restorehealth (note the space between "dism.exe" and "/" and each switch (/)).
• If DISM finds corrupted files and replaces them, restart your PC and see that improves performance.

Note
You need to be connected to the Internet to use DISM, and it might take several minutes to finish.

For more info about DISM, see Fix Windows Update errors by using the DISM or System Update Readiness tool.
If your PC is still running slowly, go to the next tip.

Adjust the appearance and performance of Windows

Windows 10 includes many different visual effects, such as animations and shadow effects. These look great, but they can also use additional system resources and can slow down your PC—this is especially true if you have a PC with a smaller amount of memory (RAM).