The Power button is also removed from the Windows Security screen, which appears when you press CTRL+ALT+DELETE. Read: You don’t have permission to shut down and restart this computer.

Read: Windows 11 Shutdown box keeps popping up randomly. Why does my computer restart when I try to shut down Windows 11? Fast Startup could be responsible for this problem on your Windows 11/10 ...

Windows 11 (or 10 ... the device will shut down automatically at the time you specified in the command. If you don't want to ...