Hello, we are transitioning our client from exchange 2003 to exchange 2010. We are in the process of moving all the mailboxes over. Unfortunately we have to do chunks at a time since we can't disrupt the users during the day. My question is, we have just migrated a test account over and tested mailflow to the mailbox. Everything looks good - however is there a way that we can get OWA to work on the migrated mailbox? We can access the mailbox via owa internally of course but I have a feeling that the migrated users are going to want to access their mailbox externally via owa WHILE the exchange 2003 and 2010 servers are still running parallel. Is this pretty much not possible? Any info would be greatly appreciated.

Yes it is possible. You will create a legacy namespace for your 2003 users and redirect all initial OWA request to 2010. Read the following links and then ask some more questions if needed. http://technet.microsoft.com/en-us/library/ee332348.aspx http://technet.microsoft.com/en-us/library/aa998186.aspx http://msexchangeteam.com/archive/2009/12/02/453367.aspx Tim Harrington - Catapult Systems - http://HowDoUC.blogspot.com

Agree with TWHarrington, Provided above link of msexchangeteam is explianing full detail how you can setup proxu for those mailbox which is moved to exchange 2010.Anil

Thank you for all sharing! Configure the Exchange 2003 URL property on the /owa virtual directory. This is necessary for Exchange 2003 and Exchange 2010 to coexist. To configure this property, use the following command: Set-OWAVirtualDirectory <CAS2010>\OWA* -Exchange2003URL https://legacy.contoso.com/exchange ThanksYour expertise never fails to impress!

Thanks for all the information. Correct me if I'm wrong, but when transitioning from exchange 2003 to exchange 2007, isn't exchange smart enoough to just send the request to the 2007 server if someone is logging in to a moved mailbox via OWA? Someone told me this awhile back.

With Exchange 2007 it will proxy through to the Exch 2003 mailbox server where Exch 2010 redirects to the Exch 2003 front end server. You would still need to point your OWA URL to Exch 2007 CAS. With 2007 you will redirect users to the /exchange virtual directory instead of the /owa virtual directory. The 2007 CAS role will need to be separated from the 2007 mailbox role. See link for more info: http://technet.microsoft.com/en-us/library/bb885041(EXCHG.80).aspx Tim Harrington - Catapult Systems - http://HowDoUC.blogspot.com

Thank you. As far as the transition goes, all that I've really done is installed exchange, SP'd it and moved over some mailboxes. I haven't done anything like configure the Hub Transport Server Role, configure send connectors, configure client access server role or pretty much anything else. Can I just go ahead and follow the articles you posted right now to get OWA working for the moved mailboxes or do I have to go further into the transition first?