How can I restart a Windows 7 computer without screen or mouse?

Hitting the power button should initiate a proper Windows shutdown.

Another option is the Shutdown command. You can either hit Win+R to bring up the run dialog, and type something like shutdown -r -f -t 00 to force a reboot immediately.

You may need to be logged in as an administrator for this to work.

Perhaps you could also create a .BAT batch file to run the shutdown.exe command, and then pin a shortcut to it to the task-bar. Once that's done you should be able to use Win + a number key related to the position to the pin on the task-bar to run it.

Check out this question for more info on that: Usage of Windows+Number combination on Windows 7

Another alternative is that you can keep hitting Alt+F4 to shutdown programs in order, and once you're at the desktop and hit it, Windows will pop-up the shutdown dialog you can navigate by KB.

Found this article that provides the following advice. Tested and works on Win7 Pro 64 but haven't tested on any other versions.

Press Windows key. Release it.
Press →→ (right arrow key twice).
Press ↑.
Hit Enter.

Also can do Windows → → ↑ R.

Use Win+R, then type

shutdown /r /f

then hit enter

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