One of our companies has repointed DNS for one of their domains to a site that is external to me. I used to have a local internal DNS zone for this that handled web and email for users that are inside the network, so I just deleted it. After flushing DNS, internal users can access the new website with no problem but when they attempt to send email to the new domain, they get an immediate bounceback from the internal Exchange server with error code 5.1.1 [SEE CODE]. It's almost like the Exchange server still thinks there is internal DNS for it, but I flushed DNS on the Exchange server and can access the website fine from there too. The email is never making it out of my network to my mail encryption appliance or spam / tls gateway.
Email from domains external to my local network flow to this "repointed" domain just fine.
email@example.com on 4/29/2009 1:59 PM
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