How to : Enabling Telnet Client in Windows Server 2008

To install the Telnet client on Windows Server 2008 follow this procedure:

• Open Server Manager by clicking Start > Server Manager, or by using the My Computer context menu.
• From the left panel in Server Manager, click on Features.
• Click on Add Features. 

• From the available list of features, scroll down and select Telnet Client, then click Next

On the Confirmation page, click on Install.

• Installation of the selected feature will be initialized and started. Once installation is completed, click on Close. 
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BTW, this can easily be done also by typing the following command in the command prompt:
Servermanagercmd –I Telnet-Client