If you receive the message:
<<Failed to Join Party.>>
BadBuild
You and a party member are playing incompatible game versions.
To resolve;
Exit your game and completely close Steam. Once you restart Steam, you should receive a message to update the game.
To completely close Steam:
- Go to your Windows taskbar
- Click the “^” icon
- Locate and right-click on the Steam icon
- Select “Exit Steam”
- Then restart Steam
Or you can close Steam in the Task Manager
- Click Alt+CTRL+DEL
- Select Task Manager
- Choose Processes
- Then locate and right-click on Steam
- Select “End task”
- Close the Task Manager and restart Steam
If you are still experiencing the issue after following these steps, please contact Customer Support for more assistance.