Login Invalid Log when console command 'open'


I have a Dedicated Server running with -log. Joining with the command ‘open’ on that server triggers somewhere a Login Invalid Log message. I guess that position in the Code is where i should put my login procedure in.
The Player joins the Server anyway.

So, where is it? Again I have to guess… Its in the Engine and not in my project right? The engine is huge, so where can I find the Console Commands? Where should I handle the Login?

Here is a picture of the log entry i mean.