C:\Documents and Settings>shutdown /?
Usage: shutdown [-i | -l | -s | -r | -a] [-f] [-m \\computername] [-t xx] [-c "comment"] [-d up:xx:yy]
No args Display this message (same as -?)
-i Display GUI interface, must be the first option
-l Log off (cannot be used with -m option)
-s Shutdown the computer
-r Shutdown and restart the computer
-a Abort a system shutdown
-m \\computername Remote computer to shutdown/restart/abort
-t xx Set timeout for shutdown to xx seconds
-c "comment" Shutdown comment (maximum of 127 characters)
-f Forces running applications to close without war
ning
-d [u][p]:xx:yy The reason code for the shutdown
u is the user code
p is a planned shutdown code
xx is the major reason code (positive integer less than 256)
yy is the minor reason code (positive integer less than 65536)
Examples :
• To shut down the local computer in two minutes and display a "The computer is shutting down" message, use the following line in a batch file or type it at a command prompt, and then press ENTER:
shutdown /l /t:120 "The computer is shutting down" /y /c
To cancel the shutdown process, type the following line at the command prompt, and then press ENTER:
shutdown /l /a /y
• To shut down and restart a remote computer named "Support," use the following line in a batch file or type it at a command prompt, and then press ENTER:
shutdown \\support /r
• To schedule the local computer to shutdown and restart at 10:00 P.M., type the following line at a command prompt, and then press ENTER:
at 22:00 shutdown /l /r /y /c
• To schedule the local computer to shutdown and restart at 6:00 P.M. every weekday, type the following line at a command prompt, and then press ENTER:
at 18:00 /every:M,T,W,Th,F shutdown /l /r /y /c
Remote System Shutdown
shutdown -r -m <
Source : http://support.microsoft.com/kb/317371