Telnet Client

Although it is not primarily a troubleshooting tool, Telnet Client is extremely useful for determining whether TCP-based network services are reachable from a client. Most commonly used network services are TCP based, including Web services, mail services, and file transfer services. Telnet Client is not useful for troubleshooting UDP-based network services such as DNS and many streaming media communications.

Telnet Client is not installed by default in Windows 7. To install it, run the following command from a command prompt with administrative privileges.

Alternatively, you can install it by following these steps:

1. Click Start and then click Control Panel.
2. Click Programs.
3. Click Turn Windows Features On Or Off.
4. In the Windows Features dialog box, select the Telnet Client check box. Click OK.

Telnet Client is useful only for determining whether a service is reachable, and it will not provide information that you can use for troubleshooting name resolution, network performance, or network connectivity problems. Use Telnet Client only after you have used Ping to eliminate the possibility of name resolution problems. For more information about Ping, see the section titled "Ping" earlier in this tutorial.