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. Run the System File Checker tool (SFC.exe)

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.

Learn how to update drivers in Windows using Device Manager to update or reinstall a driver.

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.

Download and install or reinstall Microsoft 365 or Office 2021 on a PC or Mac. Set up Office apps and email on a mobile device. Small business help and learning. Learn how to download and install apps you need from your Microsoft 365 business subscription.

Describes how to troubleshoot problems that occur when you install, uninstall, or upgrade a program on a Windows-based computer by using Windows Installer.

From the Overview page, select Office apps and on that page, find the Microsoft 365 product you want to install and select Install. To install Microsoft 365 in a different language, or to install the 64-bit version, use the dropdown to find more options. Choose the language and bit version you want, and then select Install.

Windows provides a variety of configuration tools tailored to meet the needs of different users. These built-in tools facilitate your device's customization and monitoring, allowing you to change Windows' configuration to suit your preferences and requirements with precision.

If you already redeemed a product key, you're simply reinstalling the apps, or you know you have an assigned license through work or school, you can skip ahead and go to the section sign in to download and install Microsoft 365 or Office.

Perform statistical and engineering analysis with the Analysis ToolPak. The Analysis ToolPak is a Microsoft Office Excel add-in program that is available when you install Microsoft Office or Excel.