"Session Lost"

Hello,

I am trying to connect to the server for the first time via Arma 2: DayZ Mod on steam, it shows the server when I search the IP and port, however it says "session lost" about 3 seconds after I try to connect.

Do I need to use a "DayZ" launcher? Or register to something specific?

The server is: Endless Gaming PVE....

Thanks.

Yes, you need dayZ launcher and the Epoch mod, launching from steam requires a bunch of launch parameters in order to work with the mod correctly, installing dayZ launcher will make it a simple task.