This won't solve the problem, but it may give you a useful clue: first verify whether or not your connection really is connected by doing a ping against a popular website. Open up a terminal session then enter: ping
www.yahoo.com (or whatever website you want) You should see something that resembles this:
$ ping
www.yahoo.com
PING
www.yahoo.akadns.net (66.94.230.37): 56 octets data
64 octets from 66.94.230.37: icmp_seq=0 ttl=55 time=19.7 ms
64 octets from 66.94.230.37: icmp_seq=1 ttl=55 time=17.8 ms
64 octets from 66.94.230.37: icmp_seq=2 ttl=55 time=18.5 ms
64 octets from 66.94.230.37: icmp_seq=3 ttl=55 time=18.8 ms
---
www.yahoo.akadns.net ping statistics ---
4 packets transmitted, 4 packets received, 0% packet loss
round-trip min/avg/max = 17.8/18.7/19.7 ms
$
(Do a Ctl-c to halt it.) If you don't get a response, then you can conclude that your connection is down. On the other hand, if you get positive results, then you can conclude that it's a problem with Mozilla, not your connection. If so, you should be able to get it to work by fixing an incorrect setting(s) or worst case to reinstall it. Likewise you could switch to an alternate browser such as Firefox. Like I said, this suggestion won't solve the issue but hopefully it will put you a step closer. -- J.W.