I'm about to replace an Exchange 2003 Enterprise server with an Exchange 2007 Enterprise server in a single domain. I've read the online documentation on transitioning within a single forest and understand the steps from adding the new Exchange server to moving the mailboxes/database from the old to the new server. What I'm a bit unclear about is naming. Right now our Exchange server is exchange.theirdomain.com which is what they use for webmail URL and also what the Outlook clients are configured for. During the transition I'll obviously have to give the new server a different name e.g. exchange2.theirdomain.com so the two can coexistent. So, when the transition is done and I've retired the old 2003 Exchange server and unjoined it from the domain, do I : a. rename exchange2.theirdomain.com to exchange.theirdomain.com or b. make sure there is a dns entry for host exchange.theirdomain.com pointing to the IP of the new server even though it is called exchange2 or c. change all the outlook clients to retrieve mail from exchange2.theirdomain.com Thanks.

Is this a test question? You certainly don't want to rename your Exchange server. Ideally you want to use an alias for clients to access webmail for this very reason, so I would create a CNAME record in DNS for exchange.theirdomain.com after you've successfully migrated and removed the old server from the domain. This way clients will still use the same URL for OWA.

Thanks, actually this is not a test question, it's a live domain with 100 users and I've joined the new Exchange 2007 server to the domain and will be installing the Exchange software and moving the mailboxes on Wednesday. And so yes then the answer was b. to create a new DNS record so that clients entering the name of the old exchange server will be directed to the new server.