Failed to join session (Host not found)

[Beridiia]

this happens LITERALLY (and I do mean quite literally) over 95% of the time I get invited.  I have great internet.

On top of this, when I try to invite people, I can't remember the last time I successfully delivered an invitation.

Please fix, it's been years now and I just want to get some prime parts

Edited June 24, 2017 by Waffulmann

[N64Gamefreak]

This just started happening to me several times today.  Restarting the game fixed it the first time, but just now I tried to join some clanmates for a mission: I kept getting "host not found" messages, and when I tried to invite them they both appeared to be offline.

[--Pitou--]

Same, can't be invited by anyone. Relogging didn't help.

[swiss1809]

Same issue here

[Maizaeku]

I used to get this very frequently when I attempted to play on my laptop, and the problem went away immediately after switching to a proper desktop i later built. My internet remained unchanged before and after the switch. I'm not saying this is the cause of your specific problem, but in my experience it was caused by an insufficient cpu (and/or possibly the graphics, but I'm pretty sure it was the cpu).

Presuming your problem isn't caused by a hardware limitation like mine was, allow me to give you the psuedo-fix I used back then.
When attempting to join a game with other players in the session, my game would fail to join session like yours, and i would get that exact same message. However, if I allowed my friend to start the mission and load everything properly, and -then- I attempted join, I would be able to. It takes a bit more effort but it was a solution that worked for me and may be helpful to you.