If you are still using the old school Telnet from time to time, you may be surprised when you are trying to use it in a new installed Windows 7, because it’s not recognized as an internal or external command, by default.
That’s right, Telnet is not included as a standard feature in a new installation of windows 7. To add it back on,
1. Open Programs and Features from Control Panel.
2. Click Turn Windows features on or off at the left side panel, which pops up Windows Features window.
3. In Windows Features window, enable Telnet Client by ticking the option box on.
4. Click OK to finish and install the feature.
Hurray, now typing in Telnet in the command window successfully opens the Microsoft Telnet Client in new command window.