A computer running Windows (XP, Vista, 7 or 8) with the command prompt working perfectly, i.e. not disabled by a virus.
Initial Steps
1) Press Windows Key + R.
2) Enter CMD and press Enter.
This will start the command prompt. Follow the instructions below depending on what you want to do.
Shutdown Local Machine (Your Computer)
Type "shutdown -s" without the quotes in the command prompt and press Enter. Shutdown is the command being executed and the switch -s tells the computer to shutdown.
Restart your Local Computer
Type "shutdown -r" in the command prompt and press Enter. In this case, the command switch -r is telling the computer to restart after shutdown.
Log Off the Current User
Type "shutdown -l" in the command prompt and press Enter. The -l command switch tells the computer to log off.
Shutdown a Remote Computer
Type "shutdown -s -m \\name of the computer" in the command prompt and press Enter. Replace \\name of the computer with the actual name of the remote computer you are trying to shutdown. As mentioned earlier, you must have administrative access to the computer you are trying to shutdown. To know if you have administrative access, press Windows key + R and then type the name of the computer and press Enter.
Note: If you don't remember the name of the remote computer, you can look for it by opening a list of all the computers you are connected to by executing "net view" in command prompt.
If you can connect to the computer, you will be asked to login with your username and password. Upon entering them, a window will display the list of all the directories available to you. This should help you know whether you can or cannot shutdown the remote computer.
Hibernate a Local Computer
Type in "Rundll32.exe Powrprof.dll,SetSuspendState" without the quotes and press Enter. Your computer should hibernate, if it does not, then you must enable hibernation to do this.
Shutdown your or a remote computer after a specific time
Type "shutdown -s -t 60" to shutdown your computer after 60 seconds. Upon executing this, a countdown timer displaying a warning message will be shown. This command uses the -t command switch followed by a variable (which is 60 in this case) which represents the number of seconds after which the computer will shutdown.
Display a Message containing the reason for shutdown
Type shutdown -s -t 500 -c "I am tired. I don't want to work anymore." (with the quotes) in the Command Prompt and press Enter. The -c switch is used in the code to give the reason for shutting down and what is followed in quotes will be displayed in the dialog box as the reason. This can be used to display all sorts of funny messages.
Stop a System Shutdown
Type "shutdown -a" and press Enter. This will stop the system from shutting down if the countdown to shut down has not reached 0.
