How to join in with your friends on p2p. [Update 2024]

How to play with your friends in peer 2 peer.

Instructions.

From before multiplayer with your friends was extremely different than what today's hosting looks like. Right now as for today, in Contagion we have a party system now. This party system maybe familiar with you if you played Team Fortress 2. The mechanics of this party system is pretty much similar and a lot easy than you can imagine. I'm gonna show you on how you'll be able to play with your friends. The reason why I made this guide is because I've been seeing a lot of ppl saying that they cannot play with their friends. I'll teach you all how you'll be able to play with your friends.

• 1. First things first you're gonna launch your game!
  2. Once you launch your game, you will be able to invite your friends!
  
  3. If your friends are in your party group . Click on HOST GAME
  
  4. Click LOBBY
  
  5. Once you click LOBBY , You can now set up the game however you like it.
  NOTE: Keep in mind depending on what your lobby setup PLEASE read the descriptions of what it's telling you. I can't stress this enough because like I'm telling you I've been seeing a lot of players complain that they can't play with their friends. I have not once encounter the problem with using Peer 2 Peer, (Personally I find it easier to use since I don't run into any problems with it whatsoever.)
  
  6. Now that you got your settings ready if you may now begin.
  NOTE: For your friends to join in, It will probably take a few minutes for them to actually get in your game. There should be a green JOIN GAME right next to the party system HUD, if you wanna use that as well since not all the time your friends will join in automatically. Use this command in console: cl_lobby_info that way it'll give you lobby information!

I've been waiting for a long time... What's wrong with it now?

So this seems to be most common problem now a days but this game does use Steam API Network which the lobby setup says so. You could also look at Steam Support for more imformation about Steam API. [heres the link that will tell you some information based on it: https://steamstat.us ]
I will keep in mind that There's nothing that can be fixed if you wait for too long because Steam is all behind Peer 2 Peer. There's another option you can try to use Server Reservation there's a few servers that Blue Fang Solutions provided are Lobby Only! However I doubt that you could try that with Custom Maps because those Lobby Only servers don't provide any of that.

Tips that could get Peer 2 Peer function!

- Restart the game.
- Check windows Defender before launching game since it might affect P2P
- Check your firewall to see if it’s blocking contagion.exe
Note from Contagion Developer;

"If Windows Firewall is active (which it should be, never deactivate that), make sure contagion.exe is allowing outgoing connections. If not, no peer-2-peer connection can be made, since the firewall is basically blocking it (by default, like it should).

This usually happens when the user does not allow Contagion on the firewall when they launch it for the first time (basically clicking on deny on the popup)."

- Make sure both players are set to *Online* on Steam.
- There shouldn’t be ANY port forwarding as if Contagion doesn’t use port forwarding [which could effect p2p] unlike games like No more room in hell does.
- Check if VPN is on, if it is, Disable it.
- Check out the p2p settings that's next to your profile picture in the party hud and mess around with it to see if that fixes any issues.
- If there's a password in your campaign game or lobby check it by using sv_password and make sure your friends connect to the one that has given to you or create one yourself.

Playing Custom Maps.

For Contagion, it does not have a lot of custom maps but in order to play a custom map, you need to Make sure you AND your friend both have the custom map subscribe from workshop or if you wanted to playtest your OWN map make sure you and your friend have the map in your map folder. contagion/maps Otherwise if you don't do this your friend might get an error saying map cannot be played or saying Missing map .

Other information based on Peer 2 Peer.

Thought I put some more information based on Peer 2 Peer if there's anymore thoughts that I'm not aware about:

Peer 2 Peer is getting an update because the current api file in game contains VERY old data, it still works but it’s not the best.

https://steamcommunity.com/app/238430/discussions/0/3057364366997118395/
https://www.reddit.com/r/HomeNetworking/comments/o611jk/peer_to_peer_connection_completely_severed/

[Y#shieon]

Have you tried giving someone the ip number to connect via console when you typed cl_lobby_info ?

Earlier today when I played Campaign mode with someone it randomly gave me a password? I didn't even mess with that before game started. So I guess just reset game or give them a password to join via console. It could be the cause of that but still I'm not really sure what else it could be.. Wouldn't surprised me if this also effects Lobby games.

[Suicidal Harambe]

Host of party can start a match but it never sends anyone else to Character selection, Can't join through steam either. Happens with Campaign and with lobby games. It is allowed through firewall already.

[Wuffesan]

Should add a note about Firewall.

If Windows Firewall (or any other 3rd party firewall application is installed on the machine), make sure the game is not being blocked.

You cannot make a Peer-2-Peer connection if the firewall is blocking it. (only applies to receiving connections, not outgoing)