Cancelled Connect Attempt?

[Mark]

So, after many hours of searching active VCD co-op teammate, I have ran on this problem. No matter who is hosting, we both have this problem. Any solution? Thanks.

[Dr. Cole N. Klenzer]

I used to have the same problem with a friend and I came upon this post:

http://www.runestorm.com/forums/viewtopic.php?t=78301

Here are the instructions within: "
-Close Steam
-Find the "UDKEngine.ini" file under the game's "UDKGame\Config" folder.
-Change this line: "NetworkDevice=OnlineSubsystemSteamworks.IpNetDriverSteamworks"
-To this line: "NetworkDevice=IpDrv.TcpNetDriver"

For the Host:
-Make sure Port 7777 is forwarded(which you did).
-Launch the game and host a match.

For the Client:
-Connect directly to target public IP-address using Join menu."

Note: Both players must do this and you HAVE to use direct connect.
The UDK folder is in 'Steam/Steamapps/common/Viscera"