Declude Version 4.x+

Mail server cannot communicate on port 25 to the Declude servers for Authentication and AVG updates.  After testing port access from the local server to the Declude Key manager using NSLookup, server still cannot resolve port availability. The following is an example of the NSLookup command to do this testing.

From  a command prompt, issue the following commands:

1. nslookup (enter)
2. imail.keysvr.declude.com (enter)

The final command above returns an address of 132.0.0.1 indicating that traffic to port 25 resolves successfully.

RESOLUTION

Declude requires TCP/IP communications from your port 25 for key authentication. Other than your ISP blocking traffic from your gateway, a firewall/ Proxy or router can be the likely cause of that traffic being blocked or dropped.  I suggest that you start by checking your Windows firewall and stop the service of it or any other program, such as an intrusive anti-virus or third party personal firewall.  Then issue the above NSLookup commands.

ADDITIONAL NOTES PIX

PIX in the old config (Pix V6.3.4), there is no fixup for port 25. The new version 7.x does have different commands (inspect) for this. The new version uses SMTP
AND ESMTP inspect.