Some of the following are common errors that can pop up while creating a lobby:
No server response
This error is commonly reported when TF2C cannot establish contact with the server. This can be caused by a few things.
Check the firewall of the server hosting the tf2server to make sure it is allowing TCP AND UDP whatever port the tf2 server is on, otherwise TF2C send any data to it, and you won't be able to connect to it or start a lobby. (If you are renting the server from a server provider or serveme.tf this does not apply to you.)
Lobby already exists
There are a few bugs surrounding this at the moment, but this error comes when there is a lobby from the same region as your server with the same map and config. For example..
There is already a pl_badwater with the UGC config in the NA region. If you try to create another you will get that error. It prevents a large number of the same type of lobbies appearing and taking longer to fill up.
You can choose another map and/or config type, or wait till the lobby with those specific options has started then make your lobby.
This error is reported when TF2C is able to establish a connection with the server, but the TF2 server refuses to allow the connection. The most likely cause of this is that someone has entered the wrong rcon password on TF2C enough times that it results in the server ip-banning the TF2C rcon ip for false authentication attempts.
You can find out how to fix this here.
There are already users on the server
This error is reported when there are already users on the tf2 server that you are trying to use for your lobby. If these are just some random people that joined the server because it wasn't password protected, you can ignore this and just check the box to kick users. If there are people remaining in the server after your last lobby was over, you can do the same. However, if you share the server with someone, and it says there are already users, it might mean that there is already a lobby going on with the server and creating a new one would kick everyone out, which no one wants.
I'll add more errors and how to fix them as they come up.
Edited by VoidWhisperer, 25 March 2014 - 10:33 AM.