Dawn of War Codex

So I'm getting this issue and as a result am completely unable to join any games I am invited to. I also can't see games that are up that my friends can see.

I've tried the usual fix that being, restarting the game and this hasn't helped.

Is it possible I missed a mini update or something?

The unknow joinevent is some silly Relic bug, but I think you're on the wrong version, you need 2.4.1.

Make sure you're running 2.4.1 and are not adding -dev to the launch options.

Yea, i got this bug very often as well, so i prefer to join by myself, then press invite button

Restart your game. I get this a lot and restarting the game seems to fix it

If you are in Elite and invite sended from vanillia, it happens.

Isn't this the default message when a game is full or the invite is for a different version of the game?

Not necessarily, I get it just by trying to host 2 games in a row.
First one works, second one doesn't.

I just restart and then it works out fine

It's a bug Relic introduced with one of their latest "patches"
In short they broke the invite function.
If you want to invite people, you can, but only once.
If you play a new game the invite won't work any more.
To avoid this you need to reboot your game every time you want to invite people again.