Telnet

Telnet is a command line program used to connect to public servers. Almost all operating systems include a telnet client by default. For example, you may connect to nethack.alt.org to play NetHack online by typing

telnet nethack.alt.org

It should be noted that no command line interface is quite the same as any other, and thus connecting through telnet to a server on different computers may cause strange results, especially if DECgraphics or IBMgraphics are used.

Newer versions of Windows do not come with telnet by default anymore. While a possible option is reinstalling it, most users will be better served by PuTTY; also, Windows 11 comes with ssh preinstalled, which can be accessed through the Command Prompt.

Windows telnet

Changing telnet.exe terminal emulation

Most Windows users prefer PuTTY, which can do telnet and is more feature-rich than the default telnet.exe. If, however, you're forced to use the Microsoft telnet.exe, be aware that by default it uses its own broken ANSI terminal emulation. This causes programs such as dgamelaunch to show messed up displays on your end. To fix this, set telnet.exe preferred emulation to vt100:

1. Start -> run -> telnet
2. Press 'd' and enter to display the current settings. There should be a line that says Preferred Term Type is ANSI
3. Type in set term vt100 and press enter.
4. Press 'q' and enter to quit telnet.exe; the terminal type is saved automatically.

Telnet Ports

nethack.alt.org listens on the standard telnet port. However, some firewalls block low port numbers. You may also connect on port 14321 if you can't connect on the regular port.