If some Windows functions aren't working or Windows crashes, use the System File Checker to scan Windows and restore your files. Though the steps below might look complicated at first glance, just follow them in order, step-by-step, and we’ll try to get you back on track.

If you are having issues installing or updating Gaming Services on your PC, or if you are noticing that the Xbox app for PC is launching with missing content, you may want to download and run the Gaming Services Repair Tool for PC.

Follow these steps to automatically diagnose and repair Windows security problems by turning on UAC, DEP protection, Windows Firewall, and other Windows security options and features. Select the Download button on this page.

If you cannot open your Outlook data file or suspect that the file is damaged, use the Inbox Repair tool (scanpst.exe) to repair errors in the file.

Look for Server connectivity. If the status says Blocked, your PC was unable to establish a Teredo IPsec connection to the Quality of Service (QoS) server. If you also see Teredo is unable to qualify next to NAT type, visit the Teredo troubleshooting page first to fix that problem. Go to:

To turn Microsoft Defender Firewall on or off: Select Start , then open Settings . Under Privacy & security , select Windows Security > Firewall & network protection . Open Windows Security settings. Select a network profile: Domain network, Private network, or Public network.

The Microsoft Defender Offline scan will automatically detect and remove or quarantine malware. Learn how to remove malware from your PC. Use Microsoft Defender Antivirus in Windows 10 or Windows 11 to scan your PC for malware, viruses, or other threats.

Virus & threat protection in Windows Security helps you scan for threats on your device. You can also run different types of scans, see the results of your previous virus and threat scans, and get the latest protection offered by Microsoft Defender Antivirus. Under Current threats you can:

You can start a scan for malware any time you like. Note: Microsoft Defender currently offers anti-malware on Windows, Android, and macOS. From the Microsoft Defender dashboard. If you want a deeper scan, instead of selecting Quick scan in step 3, select Scan options and choose the type of scan you want.

Manually update Surface drivers and firmware. Manual updates are useful if you need to update an offline device, update many devices that are all the same model, or if you’re creating system images for your organization.