If you want to accept an incoming Telnet connection, you must enable and run the Telnet Server service that will have access to the TCP port 23. However, in Windows Vista, the Telnet Server is not installed by default in an effort to minimize security risks and thus, you have to install it manually if you want to use it. The Telnet Server in Vista is similar to the one comes with Windows Server 2003, where it provides ASCII terminal sessions to Telnet clients, and supports two types of authentication plus four types of terminals: ANSI, VT-100, VT-52, and VTNT.
To enable the Telnet Server in Vista, simply carry out the following steps.
Enabling the Telnet Server
- Go to Start -> Control Panel -> Programs.
- In the Programs and Features section, click Turn Windows features on or off. If the User Account Control permission warning pops up, click onContinue. And if you are prompted for an administrator password, type it in.
- In the Windows Features dialog box, select the Telnet Server check box.
- Click OK and wait for the installation to finish.
Starting the Telnet Server
- Go to Control Panel, and then go to System -> Administrator Tools.
- Click on the Services applet (services.msc if you prefer to use Run command or Start Search).
- Locate the “Telnet” service, right-click on it and select Properties.
- In the Startup Type drop down menu, select “Automatic” instead of “Disabled”.
- Click on Apply button.
- Right-click on the “Telnet” service again, but this time select Start option on right-click context menu. Telnet Server service should be running after this.
- Click OK.
- Run an elevated command prompt.
- To set Telnet service to run automatically on every system startup, enter the following commands
- sc config TlntSvr start=auto (Set Start Type option to Auto).
- sc start TlntSvr
net start TlntSvr (Start the Telnet Server immediately.)
Configuration Options for Telnet Server
There are several commands that let you configure the Telnet Server. For instance, o start, stop, pause or continue Telnet server, the command syntax is:
tlntadmn [\\RemoteServer] [start] [stop] [pause] [continue] [-u UserName-p Password]
Again, to deactivate and disable NTLM authentication and switch to use only password authentication, you can use the following tlntadmin command:
tlntadmn config sec=-NTLM
Further, to make Telnet session switch to streams mode for better display of Unix/Linux clients, enter:
tlntadmn config mode=stream
You can look up more command references from the Microsoft Telnet page.