Click Start, Run and type control schedtasks
Double-click Add Scheduled Task. The Scheduled Task Wizard starts.
Under Click the program you want Windows to run, click Browse.
In the Select Program to Schedule dialog box, locate the %SystemRoot%\System32 folder, locate and click the Shutdown.exe file, and then click Open.
Under Perform this task, specify a name for the task and how frequently you want this task to run, and then click Next.
Under Select the time and day you want this task to start, specify a start time and date for the task, and then click Next.
Type the user name and password to run this task under, and then click Next.
Click to select the Open advanced properties for this task when I click Finish check box, and then click Finish.
Click the Task tab. In the Run box, specify any additional parameters that you want to use with Shutdown.exe. Click OK.
Important: In the 10th step, you need to add the parameters for the Shutdown.exe command. To immediately shutdown the system (0 second timeout), the command-line would be:
shutdown.exe -s -t 00