At our office we have an outdated Sonicwall Pro 200 and are looking to replace it. I was looking into setting up an IPCop (v 1.4.21) box with Copfilter to filter incomming emails and Dansguardian for content filtering. The copfilter addon works great, and has not imposed any problems. However, as soon as I install Dansguardian (Cop+ 2.2b3 addon), I can no longer send emails. Incomming email works corrently, and web filtering works as well. However outlook and outlook express both fail when trying to send mail with error code 0x800ccc0f stating that the connection with the server was interrupted. I have narrowed it down and found that it is Dansguardian that is blocking the SMTP connections. If I have just IPCop with Copfilter going, everything works. If I add Cop+ to the mix, SMTP quits working. I have also tried doing a fresh install of IPCop 1.4.21 and tested SMTP with nothing else loaded and it worked. As soon as I install Cop+, SMTP quits working. I need to have content filtering capabilities. I have also tried squidguard and URLFilter, however neither of them seem to function as far as the content filtering goes. They do not impede SMTP, but don't filter content either.
How do I get Dansguardian to stop blocking SMTP?