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How to resolve the various Undeliverables by Exchange 2003

Last Modified: 2013-11-30
Here's the complete error message (there are several like this)
:  sue@simplyelegantevents.biz on 10/2/2007 11:43 AM
            You do not have permission to send to this recipient.  For assistance, contact your system administrator.
            <tskorman.com #5.7.1 smtp;554 5.7.1 Service unavailable; Client host [] blocked using dul.dnsbl.sorbs.net; Dynamic IP Addresses See: http://www.sorbs.net/lookup.shtml?

The irony is we are not listed on SORBS.net, I don't know whose IP address that is (not ours).
We're using GFI Mail Essentials but I tested with that service not running and it returns with the exact error message.  I'm also checking with GFI, awaitiing their response.  Frustrating!!
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1. Go to www.dnsstuff.com and let them have check your mail server, mx records, spam lists etc.
2. Check your reverse dns records
3. If you don't have SPF, make a DNS SPF record. SPF stands for Sender Policy Framework and each domain should have a SPF record in DNS. See www.openspf.org.


The Email  Server used to go through DSL.NET until about a month ago, then these Undeliverables.


The dynamic IP listed is always the same, it looks like DSL.NET's.  Maybe I should call them now?
I went through DNSstuff.com, checked through the MX, the Reverse DNS, and spam lists - all cool.
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You have accepted my answer. Is the problem resolved?


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