Hi,
First, make sure you are connected to the Internet (obvious, but you'd be surprised).
I'm assuming you have already submitted your feed and had it approved?
If not, than that's probably your issue.
Once your feed is approved, you enter your RadioReference username and password into ScannerCast, and your feed name should appear in the
'Feed to Send' field. If it doesn't, then
1) You mistyped your login info, 2) your feed hasn't been approved yet or 3) there's an issue on RR's end.
Also, antivirus software (especially AVG), can erroneously block ScannerCast from connecting. Try disabling your antivirus/firewall, then connect again.
Hope this helps!