Background.
Our Exchange setup - we have an Exchange 2003 partially migrated over to Exchange 2010. The 2003 Exchange / server is exchange.net.0000.com and our 2010 Exchange is SVER03.net.0000.com.
We have various in house websites that has contact forms also emails out reply's etc.
Problem
In the coding of the websites in many many places the SMTP is pointing to and using our old Exchange Server exchange.net.0000.com but we will need to complete the migration and shutdown Exchange 2003. I believe this will stop many websites from emailing out. Is there a way of adding the exchange.net.0000.com to the new Exchange or a way so when Exchange 2003 gets shutdown the websites will still be able to SMTP to exchange.net.0000.com?
When you're ready to turn off the Exchange 2003 server create a CNAME record in your net.0000.com DNS zone for "exchange" that points to the A record for "SVER03".