Steam decided that you are not authorized to connect to this server

[quartz3d]

Hello,

When performing a playtest with my friend on a game I've been working on (playing against each other via a p2p connection), everything works just fine. However, as soon as we both turn on Steam, my friend gets this error message:

"Steam decided that you are not authorized to connect to this server"

Obviously, I don't get this message because I'm creating the match that he is joining. As soon as we turn off Steam, he again can join just fine. Is there are particular reason why we are experiencing this error, and how can we resolve it (I know we could just always turn off Steam, but it would be nice to not have to worry about that extra step in the future)?

Thanks,

Kevin

[quartz3d]

I should also probably point out that we were both running the latest version of Steam when he got the error....

[Shambler]

It signals that he is failing authentication with Steam; sometimes, in the current UDK, the players authentication may get stuck and the server may need to be restarted to fix that.
Try restarting the server when that happens.