We recently installed a new exchange 2007 Server. We were using an Exchange 2003 Server in the past.
Whenever we send outgoing emails to certain domain names we get an a Delivery Delayed bounce back.
When I look at the queue, there are errors relating to reverse DNS. Our FIrewall, ISP, and IP's did not change except the internal ip of the new server. There is no problem getting emails. Also I noticed that the public IP in the error messages is the main ip of the firewall 18.104.22.168, and the ip that the smtp traffic comes from is .195. The server is mail.david-feldman.com.
I put a request with the ISP to add rev DNS entries, but why would this problem surface just by changing servers.
Thank you in advance for any help.
I attached a screenshot of the queue