Use the System File Checker tool to repair missing or corrupted system ...
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)
Using System File Checker in Windows - Microsoft Support
System File Checker is a utility in Windows that checks for problems with files on your computer. To run it, follow these steps: Make sure you've installed the latest updates for Windows, and then restart your machine. To find out more, read Update Windows.
Fix problems that block programs from being installed or removed
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.
Find your BitLocker recovery key - Microsoft Support
A BitLocker recovery key is needed when BitLocker can’t automatically unlock an encrypted drive in Windows. This key, which is a 48-digit number, is used to regain access to the drive. You might be prompted for the BitLocker recovery key during startup, due to a security risk or hardware change:
How to use the PC Health Check app - Microsoft Support
Windows 11. 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.
Enable virtualization on Windows - Microsoft Support
Learn how to enable virtualization through the UEFI (or BIOS) of your PC to run the Windows Subsystem for Android or Windows Subsystem for Linux.
Recovery options in Windows - Microsoft Support
Your PC isn't working well and you recently installed an app. Restore from a system restore point. You suspect your device has been infected. Use installation media to reinstall Windows 11. Select one of the recovery options below and follow the steps to try to get things working again.
Enable TPM 2.0 on your PC - Microsoft Support
Enable TPM 2.0 on your PC. Published August 2021. This article is intended for users who are not able to upgrade to Windows 11 because their PC is not currently enabled with TPM 2.0 or their PC is capable of running TPM 2.0 but is not set up to do so.
Create installation media for Windows - Microsoft Support
You can use installation media (a USB flash drive or DVD) to install a new copy of Windows, perform a clean installation, or reinstall Windows. To create installation media, go to the software download website, where you'll find step-by-step instructions.
Ways to install Windows 11 - Microsoft Support
Create Windows 11 installation media. On the Windows 11 software download page, select Create tool now and follow the instructions to install Windows 11. Warning: Microsoft recommends against installing Windows 11 on a device that does not meet the Windows 11 minimum system requirements.