i'm having the same problem after upgrading to 1.7.3/98220; i joined another 1.7.3/98220 server without issue. repairing my vc++ 2008 installation didn't help. i've opened a support ticket. seeing these in the logs:
i'm getting the same problem as Iteration - BEC won't connect to the server after it's auto launched and dayZ commander shows the server's actual hostname instead of what i've set for hostname= in the config.