Can't join XBL parties!

There is one friends party I cannot join or play with! Anyone help?

p.s if this is already posted sorry!

Are you gold or silver membership?

I have been having this problem lately as well. I am a gold member untill march first and for some reason I can join games fine but not parties.

You and your friend most likely have Strict or Moderate NAT which won't let you two connect. You need to have Open NAT so you can join each others party.

I had the same problem for awhile. My NAT was open but still couldn't party up. I opened up some upd and tcp ports and put my modem in a DMZ and now I can join any party and find multiple games right away! :)

yeah Im gold until next month but I have just realised my NAT is strict I will open it and try again.