В статье рассказано как включить telnet-клиента в Windows Server 2008 (English).
When you first try to run a telnet command, Windows will informs you that telnet is not recognized as a command.
To enable Telnet on Windows Server 2008 follow these steps :
Open Server Manager, click Start > Server Manager
From the left panel in Server Manager, click on Features
Click on Add Features, as you can see i have not installed any Feature on this Server
From the available list of features, scroll down and select Telnet Client, then click Next to install telnet client.