Problem web-brosesr and (kerio ?)

Archived from groups: comp.security.firewalls (More info?)

Hello

I have some problems with web-browers (firefox and ie)

Sometimes, when i click on a link, i have the message "this site is
unreachable"
If i click on back button, and click again on the link, the website
appears...
I don't know if it comes from kerio firewall (v.4)

I give you the rules that i have (related with browers):

Input/Outp Prot. Local Port Distant port Action
I/O UDP all 53 accepted
I/O ICPM all all accepted
I/O UDP 68 67 accepted
I TCP/UDP all 127.0.0.1 accepted
O (a) TCP all all accepted
I/O (a) TCP/UDP all 127.0.0.1 accepted
I/O (b) TCP/UDP all all denied

The fourth first rules are from all software
The (a) rules are for web-brosers (forefox and ie)
The (b) rules are the last rules in the list (default rules)

Is my problem come from firewall, or do you think that it come for other
thing ??

Thank you !