Running SBS2003 with Exchange Server 2003.
Up until last week we had T1 voice an data Internet service with Integra Telecom.
Last week we added Comcast Business Class Internet Connection for connection speed.
Last Saturday I asked Integra to modify our MX Record to point to the new IP address given to us by Comcast. 188.8.131.52 mail.zinncorp.com
I changed the settings in my firewall to reflect the new IP address.
I tested incoming mail and it worked but did not make sure emails were reaching external recipients (my bad).
On Tuesday morning I was informed that external recipients were not getting emails.
I looked on the queue and noticed there were a bunch of emails stucked there.
I was informed by Integra that I should ask Comcast to create a PTR to 184.108.40.206 mail.zinncorp.com, this was done on Tuesday at about 11am and the said it will take 24 for the DNS Server to populate.
Today, Wednesday 6:00pm and I still have messages getting stuck in the queque.
I did tests on whatsmydns.net and everything seems to be OK.
Besides messages getting stuck in the queue, one of my users is receiving the following message when sending messages to a particular recipient.
The following recipient (s) could not be reached:
firstname.lastname@example.org on 2/23/2011 5:01pm
You do not have permission to send to this recipient. For assistance, contact your system administrator.
<mail.zinncorp.com #5.7.1 smtp;550 5.7.1 Unable to relay for email@example.com>
I have absolutely no more ideas on how to resolve this issue.
Your help will be greatly appreciated.