How are you attempting to join off of them? Are you doing it via the in-game UI? If so, try opening up your Origin Friend's list and joining via there.
There has also been some issue with the party system in the new UI. When I have been unable to join my friends, I will just look at the server they are in on the home page of the UI, and then go to my server browser and type that server # into the filter and just join via there.
em no. the trying to join friends thing was just to try if my pc couldnt find any matches. I can't join any match at all > Not via browser, not via Quickmatch/operations or via friends. :P
