Running Exchange 2003 SP2
The only change I made on my client's network was switching over from Verizon DSL to Verizon FiOS. Yes, the IP addresses are different. I spoke with Verizon and had a reverse DNS entry created for the mail servers IP. I am having an issue with a few domains we are trying to email since the switch, and also weird items in the event logs as such:
This is an SMTP protocol warning log for virtual server ID 1, connection #3. The remote host "xxx.xxx.xxx.xxx", responded to the SMTP command "rcpt" with "421 4.7.1 <email@example.com>: Recipient address rejected: Can't accept mail while inactive. ". The full command sent was "RCPT TO:<firstname.lastname@example.org> ". This may cause the connection to fail.
The items are sitting in the queue continuously retrying. Eventually they'll bounce back (though I haven't read one of the bounce back messages yet).
I am not on any blacklists whatsoever.
Any ideas? Can you help point me in the right direction?