Open up command prompt (Press the Windows Key and R button, then type cmd.exe).

Type: ipconfig /all

Scroll up until you find your main Network Adapter. Look for IPv4 Address, then look to the left. For me it would say: 192.168.1.101 (Preferred). You want that number.

Or you could use this website, they have nice guides to help you.

http://portforward.com/

the same thing is happening to me and i dont have cheat enjine. i played this a few nights ago and it worked fine. but now its doing the smae thing to me as DozleZabi. plz tell me what to do i love this game

Wow, well... It didn't work.

That's where you'd put your internal IP, which should be static. It explains somewhere on there how to setup a static internal ip.

I tried the port forward thing but I don't know what to put in the IP address box

There are still a number of servers that haven't upgraded to .35 yet, although it would be a long shot to assume you tried only to join those servers. Portforwarding ports like 32887 or 80 might help (portforward.com), but I'm not entirely sure. It takes a small effort to do that, so it's your decision if you want to attempt.

There isn't a .folder that starts with CT

What I do know is if the 'true' .CT is highlighted then under the data tab it will say 'Cheat Engine.'

I don't know how to do that router thing.

There are other registry entries that may contain .CT that aren't Cheat Engine. You might want to go and look for other entries. Even a string that BEGINS with CT may affect being able to join a game If I am not mistaken.

Are you using a Router? You need to forward your ports through the router as well. Router's have an internal firewall.

like I said, I never downloaded cheat engine.

and just for fun I looked in that HROOT thing and there was no folder in the list called .CT

Shouldn't that registry only appear if cheat engine was actually installed? OP clearly stated he has never downloaded it before.

Even with uninstalling Cheat Engine, it will still cause you to error out. Here's the original post with the solution (if you have, or ever have had Cheat Engine installed):

Okay if you've updated to the latest version as of this day (Which would be version 0.35), and you are getting the error:
Quote

Server connection failed: Version mismatch or map transfer fail

On every single server (not just full servers), ever since this update. Then this should fix it for you.

Open up the Registery Editor (Open the run window [Windows Button + R], and type in: regedit).

Go to: HKEY_CLASSES_ROOT, and look for the key in that list named: .CT

Delete it, and the error should be fixed. If not, let me know.

I used Internet Explorer and it started working fine and make sure you don't have cheat engine.

It goes black screen for about 10 seconds, then my cursor disappears for 20 seconds, reappears with the error and the game closes

Does the map download partially before the error occurs or does it automatically start with the error? Does it even go to the black screen first?

My antivirus is set to allow all for the server.exe and client.exe

and it still isn't working

You could check your firewall/antivirus to make sure it isn't blocking new connections for some reason from the client.

My internet connection is fine. I've never had slow internet and I can play many online games just fine with no lag.

It could be your internet connection, then.

Note: NO I HAVE NEVER OWNED OR DOWNLOADED CHEAT ENGINE

I cannot seem to connect to any server no matter what and I keep getting the map transfer/version mismatch error

I have tried all my browsers

I have the updated version

I have tried everything there is including re-installing the game.