IPCop - Browsing to mail server through VPN
I have two sites, one hub Site A, and a spoke, Site B. Site A, 1.4.10, site B 1.4.18. I installed 1.4.18 last week (new hardware) at Site B, set up vpn to hub and was able to get to hub site's mailserver via port 80 for hours with no problems. This week, no one from site B can connect to the mailserver at site A through the browser (Firefox or IE) - just times out, no error. I checked the firewall logs and they show workstations at site B trying to connect to the mailserver through the VPN but with lines that say "New NOT SYN?" per connection.
From the day I got 1.4.18 running on site B, the only change to the config there was that I added Adv proxy and URL filter, though, my remote tech box at Site B which is excluded from filtering and still cannot get to the mailserver through the VPN.
Site B had been tested prior with 1.4.10 and 1.4.13 on different hardware and the result was that NO workstations could ever connect to the mailserver. That is why I installed 1.4.18 on a new(er) computer last week.
My next idea is to wipe out the box and start fresh with no add-ons and see how long the workstations can get to the mailserver, though, this problem has plagued me at other spoke sites for years.
Any ideas? Anywhere I can look to determine why the connections are not being made?