i setup a microsoft small business server 2003 using network solutions for dns hosting. i enabled smtp logging because of this problem, incoming email to our domain has no problems. i could also email tons of other domains no problem as well.
it seems like when my domain emails a domain that uses appriver or mxlogic as their spam provider emails intermittently bounce. i found a pattern of the problem in my smtp log. anytime our server connects to their website IP (which it shouldn't in the first place right?) email bounces back with User Unknown or Relaying Denied non delivery reports. (of course it will bounce back because the user probably doesn't exist or that mail server could be running but not accepting mail.) why would it connect to their website IP and not their MX record IP? my exchange server looks up another domains email server by mx records right? it can't get it wrong can it?
if it connects to their spam provider first then mail gets delivered ok. the IP of domains that i get the bounced mail from i could telnet into port 25 and it responds back as a mail server of some sort... it could be their old server but why would our exchange server connect to their old website/mail server instead of their new mail server/MX record?
is this a problem with my mail server or do they have outdated dns or mx records somewhere?
November 12, 2007 11:58 PM
November 14, 2007 6:01 PM