I just picked up Rainbow Six Siege over the weekend and hoped to play with one of my friends, instead we keep getting this error message when trying to join each other:

Error Code [2-0x00000067]

We both haven an Open NAT and both on XB1. We're able to connect in XBL party chat without issues. My UPnP is open and I even have a PPPoE connection setup with my provider to ensure that I have a public IP address.

I've tried power cycling both the router and the XB1 without any luck. I never had these issues with The Division Alpha, and despite numerous issues with Destiny servers, I was always able to join my friends in gameplay.

What's going on with this error? I see LOTS of people posting they have it - but nothing in the 'known issues' section of these forums, and no acknowledgements from Ubisoft in any of the threads. What gives?