Exchange unable to receive from 1 domain

[TheCoach]

Hello,
SBS 2003 with Exchange sp2.

Unable to receive email from one domain (that I know of).


We are on no BLs; we have rDNS in place.


They receive no NDR.


Problem domain uses St. Bernard for email filtering incoming and
outgoing. SB sees the email sent to our email address and sees no
issues. (To me, it seems like it could be dns resolution
issue...maybe I should have asked SB to do an nslookup...forgot and
now on hold again!)


I don't see anything in the server log (I'm looking in C:\Program Files
\Exchsrvr\SERVER.log and seeing other successful emails....please let
me know if I should be looking somewhere else.


I inherited this server and it is multi homed running RAS firewall.
One NIC connnected to the router fromgroups.google.comocal network
switch. I don't know if this could be blocking for some reason, but I
don't see any indication of that.


Any ideas appreciated.

[Connect_Me]

Hello Have you confirm Exchange message tracking? Is the message inflowing the message tracking? Do you encompass third party spam filter? Do you include Exchange Filtering Set up? Did you check Connection Filtering, Intelligent Message Filtering? And in addition Is the sending domain's IP resting on whichever RBL's? Can the sender telnet on top of port 25 commencing their IP in the direction of your Exchange Server? Please check all this settings and if you don’t know how to setup this then search it on internet and according to that make changes in these settings. Thank you.