If it happens that your Windows Server 2003 is stuck and/or you don’t have access to remote desktop connections to access it, you can restart the server remote, from another Windows server, via command prompt:
Shutdown /m \\computername /r /c “Remote Restart” /t 45
where: t 45 , is amount of seconds to wait before restart
c “Remote Restart” is the reason (it will be logged)