Enable Telnet on Windows Server 2003

Windows Server 2003 has the Telnet disabled by default (and so good that it does!) To have the Telnet service running on Windows Server 2003 follow the next steps:

1. Go to the Services applet in Administrative Tools (or click Start, then Run, and type "services.msc" (without quotes) and click OK).
2. Find the "Telnet" service, right-click and select Properties, select "Automatic" instead of "Disabled" in the startup type box.
3. Click Apply.
4. Right-click the "Telnet" service and select Start.

5. Click OK.
You can also modify start state and start it from a Command Prompt console by using the following command: "sc config TlntSvr start= auto" and "sc start TlntSvr" or "net start TlntSvr"
Configuration for Pre-W2K/XP/2003 Clients:
The Telnet server requires NTLM authentication by default. To deactivate this and use only password authentication, use the tlntadmn command: "tlntadmn config sec=-NTLM"
Also, switching to streams mode may make display easier for Unix/Linux clients. Do this with the following command: "tlntadmn config mode=stream"

Enabling Telnet Client in Windows Server 2008
Enabling Telnet Client in Windows Vista