How to Fix Teredo Problems

Teredo is a networking protocol for some titles, to establish a connection to the Xbox network multiplayer services on Windows PCs.

Games that use Teredo include:

• Forza Horizon 3
  
• Forza Horizon 4
  

• Gears of War 4 (for Online Co-op capabilities)
  

If you are receiving the error that Teredo is "Unable to Qualify,” or you are experiencing frequent multiplayer connectivity issues with these titles, the following Xbox support articles may help.



Are you seeing a message like "Teredo is Unable to Qualify?"

If you are receiving the “Teredo is Unable to Qualify” error when checking your Xbox Network Connection, start with this article.



To keep your Windows device working properly, carefully follow the instructions listed in the article.

Not receiving a specific Teredo message?

If you are not receiving the specific Teredo error message but are still experiencing an issue connecting with the games listed above, please start with this article.

Some things to keep in mind:

• Third party applications do not have to be just security software programs. These can include anything that changes your personal computer’s registry settings, like anti-virus/malware programs and PC optimization programs. You may need to go through the troubleshooting steps for each program identified.
  
• Your connection may be blocked by your router. Check the support resources or documentation for your specific router on any material relating to providing a Teredo connection or port 1026.
  

Still can't connect?

If you are still experiencing the error after using the above support articles, there are outside factors that could result in the issue persisting. For example, one possibility is that your internet service provider (ISP) is blocking port 1026. Even if you have already opened this port, if your ISP is blocking it then you will continue to experience server connectivity difficulties.



The Microsoft engineering team was able to reproduce and fix the Teredo-related problems using the updated troubleshooting steps provided in these articles. If you want to continue troubleshooting, we recommend that you contact your ISP for more personalized solutions to try.

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