How To Use Telnet On Windows

How to Enable Telnet on Windows 10?

In Windows systems, Telnet is disabled by default. To check if Telnet is already activated, open your command line, and run telnet:

Telnet not a recognized command command prompt output

If the command prompt does not recognize the command, there are two possible ways to enable the Telnet client in Windows.

Option 1: Enable Telnet using GUI

To activate the Telnet command using the GUI:

1. Open the Programs and Features options in Control Panel:

Programs and Features option in Control Panel

2. Click the Turn Windows features on or off setting:

Turn Windows features on or off setting in Programs and Features

3. Locate the Telnet Client option on the list, select it and click OK to install the feature:

Windows Features list with Telnet Client

4. When Windows completes the requested change, click Close.

5. Open the command prompt and run telnet to open the Microsoft Telnet Client:

Microsoft Telnet Client running

6. Run quit to exit the Telnet client.

Option 2: Enable Telnet Using Command Prompt

To activate the Telnet client from the command prompt:

1. In the command prompt, run:pkgmgr /iu:"TelnetClient"

2. Restart the command prompt and run telnet to open the Microsoft Telnet Client.

3. Run quit to exit the client:

Exiting Microsoft Telnet Client with the quit command

How to Use Telnet in Windows to Test Open Ports

The Telnet syntax for testing open ports is:telnet <address> <port number>

The command accepts both symbolic and numeric addresses. For example:telnet 23

Or alternatively:telnet 80

After running the command, one of the following three options happen:

1. The command throws an error, indicating the port is not available for connection:

Error message for telnet port

2. The command goes to a blank screen, indicating the port is available.

3. Running the command on an open port 23 displays the screen of the telnet host, confirming an established Telnet connection:

Telnet established connection login screen