What Is Teredo?

Teredo is short for Teredo tunneling, in this context. Think of Teredo as a translator between different versions of the Internet Protocol (IP), specifically version 4 (IPv4) to version 6 (IPv6.) The entire internet is slowly upgrading to version 6 over time, but that leaves many people using the outdated protocol. Teredo tunneling is used in situations where one endpoint of the tunnel is private, such as behind a router. That way, it can translate smoothly between the two protocols, allowing them to share data.

What Does ‘Teredo Is Unable to Qualify’ Mean?

This error means that the Xbox was unable to secure a Teredo IP address. In other words, it’s unable to determine where it should send internet traffic. 

When Does My Xbox Use Teredo?

Teredo tunneling is only used for in-game chat and online multiplayer features. Other online features, such as video streaming and using the online store, are generally unaffected, so you may not notice the error until you use these features.

How Do I Determine If My Xbox Is Using Teredo?

Generally, Teredo use is determined by your internet service provider’s choice of protocol. Checking your IP address online, or in the settings of a computer connected to the same network as your Xbox, tells you whether you have an IPv4 or IPv6 connection. These are two separate IP addresses; if there’s no IPv6 connection, then you are on IPv4. If you have an IPv6 connection, it connects directly.

What Causes the Xbox Teredo Error?

Xbox Teredo errors are usually connection errors that masquerade as something more complicated. The error often pops up when something gets in the way of an Xbox getting online, meaning an issue in your home network, not something on Microsoft’s end. It can be a simple Wi-Fi issue, a missed update, or something with the home network configuration.

How to Fix the Xbox Teredo Error

Now that you understand what Teredo is and how it works, you can troubleshoot issues that may arise if you experience the “Teredo was unable to qualify” error. Here are some things that might help: