I figured someone else might come across this problem, so hopefully this information will help. I was trying to diagnose a problem with my Dad's email account, and in doing so, wanted to try to Telnet to the mail server to get more information about the problem. It sounded like a straightforward thing to do, but it seems Vista doesn't recognize the 'telnet' command. By default, Vista doesn't come with Telnet installed, so here's how to get it.
Go to 'Start->Computer' and then click 'Uninstall or change a program' that should be on the button bar at the top. Then click 'Turn Windows features on or off' and after you click 'Continue' on the security prompt, you should see a list of components. Scroll down to 'Telnet Client' and check it. When you click 'Ok' it will install it for you and you should be all set to Telnet to your hearts content.
