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.

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.

Each release of the tool helps detect and remove current, prevalent malicious software. This malicious software includes viruses, worms, and Trojan horses. Microsoft uses several metrics to determine the prevalence of a malicious software family and the damage that can be associated with it.

Blue Screen errors (also sometimes called black screen errors or STOP code errors) can occur if a serious problem causes Windows to shut down or restart unexpectedly. You might see a message that says, "Windows has been shut down to prevent damage to your computer" or a similar message.

The Program Install and Uninstall troubleshooter helps you automatically repair issues when you're blocked from installing or removing programs. It also fixes corrupted registry keys. First, you'll need to download the troubleshooter. Download troubleshooter.

You can repair some apps and programs if they're not running correctly. Note that you won't see repair, change, or modify options for all apps and programs. Repair options from the Settings page. Select Start > Settings > Apps > Apps & features. Apps & features in Settings.

If a Microsoft 365 application such as Word or Excel isn’t working correctly, sometimes restarting it will fix the problem. If that doesn’t work, you can try repairing it. When you’re done, you might need to restart your computer. The steps to access the repair tool vary depending on your operating system.

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.

PC Health Check app brings you up to date info on your Windows device health, helping you take action to improve your device performance and troubleshoot performance problems. It is periodically updated based on customer feedback to help you make the most of your Windows PC. How to open PC Health Check. In Windows, use Search on the taskbar to ...

The .NET Framework Repair Tool provides an option to repair the versions of .NET Framework that are installed on the computer (step 3 of the process in the "Repair Tool options" section). The tool requires the redistributable files of those versions to be available at the time of repair.