Have your users authenticate on Port 587 for SMTP and change your firewall to only allow Port 25 traffic to your Proxy. I'm not sure which version of Imail includes Port 587 for SMTP Auth. We're running 8.22 and it is included in that release.
Tuesday, December 27, 2005, 11:23:45 AM, Adam Winter <[EMAIL PROTECTED]> wrote: AW> I'm using version 8.05 and the spam filtering capability of that version is AW> becoming ineffective even with the Anti-spam updates. I have put in place a AW> 3rd party spam server proxy which incoming email gets sent through for AW> filtering and then relays to the Imail server. The spam filter does subject AW> modification, so in Imail I use a rule to check for either the X-header from AW> Imail or the modified subject to determine if it should go to spambox or AW> not. AW> Here's the problem. After changing the MX record, spammers are still AW> sending email directly to the Imail server because they either know it AW> already exists, or their DNS servers cache the old MX record forever. I AW> can't shutoff access to Imail's external IP address, because legitimate AW> users of about 100 domains still go there to send their email and require AW> SMTP access. AW> Solution (in theory): I need an Imail rule which either detects the AW> presence of the spam filter proxy's IP address in the header (easy) or can AW> tell if the email was sent by an authenticated user (impossible, as far as I AW> know). Any email other than those 2 exceptions would be classified as spam AW> because they didn't go through the proper channels. In effect, no email AW> would be received by users by sending it directly to the Imail server. The AW> problem is that users of one domain could not email users of another domain AW> hosted on the same server because they didn't go through the spam proxy, nor AW> can authentication be determined. AW> So, I'm wondering if 1 of 2 options exist: AW> 1. Can authenticated email be identified somehow with a rule? AW> 2. Can an X-header be inserted on outgoing email? AW> Thanks for any ideas! AW> Adam AW> To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html AW> List Archive: AW> http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ AW> Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/ ---- Don Brown - Dallas, Texas USA Internet Concepts, Inc. [EMAIL PROTECTED] http://www.inetconcepts.net (972) 788-2364 Fax: (972) 788-5049 ---- To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/
