"problem with provider" message when firewall up
when eip is trying to stablish a connection and the firewall is up (after quitting and not bringing fw down), the message displayed to the user is "problem with provider". we should instead try to detect if the firewall could be avoiding us from reaching the internet.
(from redmine: created on 2014-05-08, closed on 2014-06-10, precedes #5588 (closed))