This is due to a decision by Microsoft to make some very ( in my opinion ) stupid decisions regarding Teredo, IPv6 and uPNP. From their Website : http://download.microsoft.com/download/A/C/4/AC4484B8-AA16-446F-86F8-BDFC498F8732/Xbox%20One%20Technical%20Details.docx https://drive.google.com/a/hatrixsec.com/file/d/0B7YucBK7CMjGV0Y0NEotbWtBY1U/view?usp=sharing_eid I am going to put it on my google drive because I have no doubt they will delete it once it becomes obvious what morons they are. SAVE this file and view it with M$ word or their viewer. That way you can virus scan it. It is un-altered I assure you. BUT... just to so you know it is safe, I am doing it this way. ( Unaltered - not exported - or tampered with in anyway ). Some of the more salient points that I have gathered directly from this document also GOOOOGLE " christopher palmer microsoft xbox one " .. entertaining stuff. [b]Allow UDP[/b] Teredo uses UDP to create port mappings in NAT equipment and to communicate with Teredo peers. RFC 4787 and RFC 6888 provide recommendations on UDP behavior of network equipment. Sections 4-6 of RFC 4787 are especially relevant to network operators and equipment vendors. [b]Configure open NATs, avoid symmetric[/b] RFC 6081, Section 3, provides a connectivity matrix for Teredo. In general, cone, address restricted, and port restricted NATs, work fine with Teredo. Networks that block UDP traffic will not support P2P gaming. The more “open” a NAT, the more likely the user will be able to communicate directly with others, and in general the better experience the user will have. What they completely missed was that Toredo will not play nicely with uPNP on 99% ( I bet 100% ) .. of routers. There are people that say they got it working with DMZ, Punching Holes in Firewalls, Triggering and VLANing.. I am not convinced at all that any of these techniques work at all. I have spent a TON of time on this, since it means I am not able to able to talk reliably to one of my offspring while we play Destiny. Titanfall was better, but that's a whole different gig with IPsec and Azure. ANYWAY.. If anything does work .. it would/might be to open up your xbox one's to the internet by setting up firewall rules to allow full access, and I am not trying that, thank you very much. Bottomline.. they need to undo what they have done in the document mentioned above, OR get teredo to work right with uPNP .. i.e. ask for random ports please. NOT 3074 .. ALL THE DAMN TIME. FFS. The supposed fallback also doesn't work. I have the firewall logs to prove it. Open NAT/Closed NAT/Restricted/Cone/Secure all mean NOTHING if 2 XBONES are on the network at the same time since they both contend for the same port CONTINUOUSLY. it's all BS to hide this other cr@p above. Class action is the next thing we need to do. Anyone game ? #upnp #twoxboxes #miniupnpd #routing #chat #issue #teredo #coned #restricted #moderate #strict #network