well are you connected to the computer you wish to shut down with telnet, or are you still trying to remotley shut it down with out using telnet? This entire thread is about using telnet to connect to the computer, loging in, and then shuting that computer down. If you try to remote shutdown using "shutdown -m \\computername" its just going to return you to the command line with "access denied". What you need to do is connect to the computer you wish to shut down, login with a vaild username and password combination, and type "shutdown -s" into the command line which will then shut the computer down.
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