Content Server authentication issue

I have the content server up and running, but cannot get past the user authentication. I've tried setting the fields in Preferences to blank or filled and I still can't get in. Suggestions?

BTW, I have made sure I'm using the correct IP address and the tablet I'm using also has access to my at home network (same as the laptop that has Calibre). I did have to change "8080" to "80" in the Preferences to even get to the authentication screen. Prior to that, it simply timed out.

Thanks!!!
Judy