Known Problems and Solutions

Problem: Telnet links do not work in Windows Vista

The Windows Vista operating system is distributed with its telnet function uninstalled.

Solution: Microsoft's Telnet: Frequently Asked Questions page describes how to install telnet in your Windows Vista system.

Problem: Internet Explorer 7 does not open telnet links

Microsoft removed support for telnet in IE7. This version of the web browser does not let you follow telnet links.

Solution
You can make a simple, one-time modification to enable telnet usage in IE7. This process normally takes less than a minute. Follow the instructions below to download a file that edits your computer's registry information.

1. Click on this link to IE7_telnet.reg.
2. You will see this window (exact wording and appearance may vary):
   
    
   
   Click on Run.
3. You will see this window:
   
    
   
   Click on Yes.
4. You will see this window:
   
    
   
   Click on OK.
   
5. Close your IE7 browser.
    
6. Open a new IE7 browser.

Problem: Firefox does not open telnet links

Some users have reported that when they click on a telnet link, Firefox responds with a prompt to "launch an external application."

Solution 1

If you see a pop window which states an external application must be launched to handle telnet links, do the following:

1. Check the box for "Remember my choice for all links of this type.
    
2. Click on "Launch Application."

 Your telnet session should begin, and you should not receive the warning prompt again.

Solution 2

 This applies if you do not see the pop-up window shown above.

1. In the Firefox address bar, type about:config [no spaces]
   You will see a list of configuration settings.
    
2. In the "Filter:" box at the top of this list, type: telnet
   You should see:
   network.protocol-handler.warn-external.telnet   user set   boolean   true
    
3. Double-click on the word "true" and it should change to "false".

 You should now be able to follow links to telnet systems without interruption.

Solution 3

This applies if you do not see either the pop-up window shown in Solution 1, or the configuration setting identified in
Solution 2.

1. In the Firefox address bar, type about:config [no spaces]
   You will see a list of configuration settings.
    
2. In the "Filter:" box at the top of this list, type: telnet
   No configuration settings appear.
    
3. Windows: Right-click anywhere in the main part of the browser window.
   Mac: Control-click anywhere in the main part of the browser window.
    
4. In the pop-up menu list hover the cursor over New.
    
5. In the fly-out menu list click on Boolean.
    
6. The New Boolean value window will prompt you to "Enter the preference name."
    
7. Type or paste network.protocol-handler.warn-external.telnet into the New Boolean value window. Click on OK.
    
8. A second pop-up window will appear and prompt you to enter a Boolean value from a list that consists of "true" or "false." Click on false.
    
9. Repeat step #2 (in the "Filter:" box type telnet).
    
10. You should see:
    network.protocol-handler.warn-external.telnet   user set   boolean   false