Try returning to Orbit, waiting a few minutes then return back to the Reef, as Bungie suggested on Twitter: https://twitter.com/Bungie/status/672817989784219648 It may take several tries. Please be patient. Closing and restarting Destiny might work around the issue with Xûr's door closed as well. Please follow this instruction to resolve the issue. If it does not work immediately, please try it again at a later time. Try waiting half an hour or play a Strike inbetween. Additionally, Clearing your console cache, re-logging into your character again and joining a Reef instance might help resolving the issue. Bungie is aware of the issue. We are sorry about the confusion. Edit: Xûr has been relocated to the Tower.