I've had this same problem since April as well. Bungie has never replied to any of my posts about it. What I can tell you and everyone else here is that it is NOT a router/ISP/NAT/port/live account/settings problem. The problem is with Bungie and the way they authenticate your gamertag with Microsoft. For some reason, some accounts are not being authenticated correctly. What is infurating is Bungie's complete lack of communication and help in regards to this issue. It's been ongoing for 4+ months for some ... let that sink in ... OVER 4 months with ZERO acknowledgment or communication on Bungie's part. But they have time to partner with drink companies, patch things that they consider to be cheese, market their upcoming expansions, Luke Smith us all to death, Twitch Stream, attend E3, make a t-shirt launcher .... The list of uselessness goes on and on. Your priorities are so far from what sane, rational people expect no wonder the internet is burning with Bungie rage. Respond to any help questions within 24 hours. Do not ignore issues. STOP blaming your customers for issues that are your fault. Do not give cookie cutter responses to serious questions. Communicate respectfully with your customers. Fix game breaking issues ASAP. And refund/reward those customers who have been loyal enough to ask for help, while being denied for months on end from playing the game.