Connection Issues: “Additional authentication needed

Follow the link on the comments I had the same issue and it worked like a charm!!

Thank you for contact us! I'm Anderson, an Independent Consultant and a Microsoft user like you.

Good morning

How can i help you?

Hey there DeRo!

Sorry to hear you are running into this issue, I have found a separate forum with a solution posted, I am going to link it here so that you can go ahead and follow some troubleshooting steps.

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Running into the Additional authentication needed message? Check here!

Go ahead and follow the link and let us know if this has worked.

Are you connecting your console to a hotspot, or a guest network at a hotel, which are secured by a captive portal (authentication web page)?

The second option require you to spoof the MAC address of an already associated/authenticated/authorized device and not the MAC address of whatever interface you're using to connect your Xbox (ethernet/wireless).

Also, make sure you're not concurrently connected with the current associated/authenticated/authorized device and your console, as they use the very same layer 2 identity.

Hi Kevin,

Every hardware device that connects to a network has an identifier code that is called a MAC address. This is how devices recognize each other because every device has a set and unique MAC address, unlike an IP address that cycles and changes periodically.

If I'm not mistaken the additional authentication required is your internet provider asking for your Xbox's MAC address to add it to the approved list of devices that your router allows to connect to. When you select the authenticate now button, it will
not load the page since it's trying to load a secure site that your ISP would authenticate the MAC address by first signing in to your router settings.

We have seen higher instances of this happening with AT&T for some reason, but essentially you need to make sure with AT&T that your Xbox is not being MAC filtered out from your router.

Before contacting AT&T, I suggest troubleshooting the console's MAC address and see if makes the Xbox more discoverable. Go to Settings>Network>Network Settings>Advanced Settings>Alternate MAC address>Clear and then select Restart Now when prompted.

If that doesn't work, call AT&T and ask for assistance with making sure your Xbox is not being filtered out. The console's MAC address can be found under the Advanced settings so have that ready when contacting your provider.