When things go wrong and Windows doesn’t work, you can repair, restore, or recover Windows by using tools that Windows offers. Tools like System Restore takes "snapshots" of critical system files and some program files and registry settings and stores this information as restore points.
If your computer is not functioning correctly, you can use these restore points to return Windows to a previous state when your computer was functioning correctly.
Use System Recovery and Repair
This simple guide will help you work through which tool to use and what steps to take if Windows won’t start, something changed that you don’t like, it only starts in safe mode or you are being asked to run the Memory Diagnostic tool.