Create A Scheduled Shutdown Via Script In Windows
I often use this command to create a scheduled shutdown. You could also use to run any program you want.
schtasks /Create /SC daily /RU DOMAIN\user-account /RP myPassword /ST 18:00 /TN Auto-shutdown1800 /TR "%windir%\system32\shutdown.exe /s /f"
Just replace your username, password, and give it a unique name.
To remove it, you can delete it by its name:
schtasks /Delete /TN Auto-shutdown1800 /F