I just migrated my domain Exchange 2003 version to Exchange 2007 into a new Windows 2008 64-bit server. After the initial installation, everything seemed to be working, but as soon as I move a mailbox from the old 2003 server to the new server 2007 server, Outlook Web Access (OWA) displays a "403 - Forbidden: Access is denied" error. Otherwise, all other functions seem to be working (POP, native Outlook, etc), except for the Exchange Attendant system that won't start automatically (not related I think). OWA also works for mailboxes that have not been moved yet.
I now have two Exchange servers (1x 2003 on w2k3 and 1x 2007 on w2k8) with two distinct IIS installations (IIS 6.0 and IIS 7.0) and the error message is the same whether I try to connect to the old server OWA or the one from the new server (with a mailbox that has been moved). The only customization done to the new IIS web server was the addition of a "binding" name (mail.xxx.com) on the Default Web Site. Of course I still have to migrate smtp, pop, etc. services and decommision the old Exchange 2003 server but I'd like to have everything working out of the Exchange 2007/Windows 2008 server first (I am also migrating the web server to this new server).
So, if I try to access OWA with a mailbox/account that has not been moved to the new mail server, everything works fine. Why? I did a pilot project a few months ago and never got this behavior.
Thanks in advance.