How to Set Your Computer to Shut Down at a Certain Time
While you can set a computer's power management utility to have the machine shut down after a set amount of inactivity has passed, scheduling a shutdown as an actual system event ensures the computer will power down no matter what process may be running on it. And using the Windows Task Scheduler, you can schedule your computer to shut down at a certain time and date--you can even make shutting down a recurring event.
Windows Vista and 7
Click on the "Start" button and then type "Task Scheduler" in the Start menu search box. Click on the Task Scheduler icon when it appears in the Start menu.
Click on the "Create Basic Task" option in the Task Scheduler to open the Task Creation wizard. Enter a name and description in their respective fields in the wizard. Click "Next."
Select a recurrence option for you scheduled shutdown from the list of option below the "When do you want the task to start?" heading. Click "Next."
Select a date and time for your shutdown, using the fields next to the "Start" heading. Click "Next."
Ensure that the "Start a program" option is checked on the following page--it should be selected by default--and click "Next."
Click on the "Browse" button to locate your computer's "shutdown.exe" file (C:\ Windows\System32\Shutdown.exe). Click "Next," and then "Finish" to schedule your shutdown.
Launch the "Add Scheduled Task" wizard from the Control Panel's Scheduled Task utility.
Click "Next" on the wizard's welcome screen. Click "Browse" on the following page and locate your system's "shutdown.exe" file (C:\Windows\System32\Shutdown.exe). Click "Next."
Select a recurrence option for your schedule shutdown from the options listed under the "Perform this task:" heading. Click "Next."
Select a start day, time and month options on the following page and then click "Next." Set an optional password for your event on the following page and then continue to the end of the wizard.