Question : 530 error bounced email when sending to any sbcglobal.net address from our sbs 2003 server.  The ISP is sbcglobal DSL line.

Hi,

I have a newly setup SBS 2003 server that can't send any email to a sbcglobal.net  email address.

Ex bounce message:

The following recipient(s) could not be reached:
     [email protected]et on 7/26/2010 10:19 AM
            The message cannot be delivered due to a configuration error on the server. Please contact your Administrator.
            <williamslawpc.com #5.3.0 smtp;553 5.3.0 flpd240 - o6QFJCKs021280, DNSBL:ATTRBL 521< 68.94.155.105 >_is_blocked.__For_information_see_http://att.net/blocks>

I've contacted AT&T/Sbcglobal but they have yet to reply.  All other email works.  To add to the confusion one user has a sbcglobal.net email address that he refuses to give up.  We pop his mail down and rewirte the email address to mask the willamslawpc.com email address.

Outbound email is send via DNS.  Do I need a smarthost?  Can I set up a smart host that will work only if the email is targeted at sbcglobal.net addresses?   Will other AT&T domains bounce as well? Bellsouth, pacbell, etc.

Answer : 530 error bounced email when sending to any sbcglobal.net address from our sbs 2003 server.  The ISP is sbcglobal DSL line.

Go here
www.mxtoolbox.com
enter your domain name

Run SMTP Diagnostics and Blacklist Check

SMTP Diag gives
RDNS Failed
http://mxtoolbox.com/SuperTool.aspx?action=mx:williamslawpc.com

a) Check with your ISP if they can add PTR records for sbs.williamslawpc.com
b) Configure RDNS on Exchange 2003
http://www.amset.info/exchange/dnsconfig.asp

Your blacklist check is fine.

thanks