Why can't I open my start menu after installing Windows 10?

[Windows Central Question]

After installing Windows 10 in August around mid September my start menu stopped working. It gives me a critical error and says it needs me to sign out to work the issue but it does not work. For more details, I have a dell laptop that previously had windows 8.1. I have searched countless forums on how to solve the issue but I am still not able to open my start menu, open the app store, nor use the icons in my taskbar. Does anyone have a solution for this?Thank you.

 

[xandros9]

Try Ctrl Alt Del and get Task Manager.

Run cmd.exe as administrator.

Try the sfc /scannow command.
You can Bing that for more information.