After solving my server-publishing problem through a second firewall in an array, I have discovered what appears to be a problem with the SMTP message screener. With the message screener enabled, users on the outside of the firewall are unable to authenticate with the SMTP service to route mail (pop works fine). Disable the message screener and everything works fine.

I located Microsoft article number Q295164 that pointed me in the right direction û until then I was back at the hospital again for all of the bruises on my head. The interesting thing (maybe slanted is a better word???) is that the article I referenced above only refers to Cisco firewalls & makes no mention of ISA server as being a problem. I did verify by using a fix-break-fix process that the message screener is the culprit.

Has anyone see this??

Any work arounds??

The only think I can think of is either an additional firewall dedicated to supporting external mail clients that is not a member of my array (an administration PITA), or a fix from Microsoft. Anyone from Microsoft listening????

AUTH and the SMTP filter do not work together. If you need authentication access to published SMTP servers, you'll have to disable the SMTP filter.

HTH,
Tom

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