http://www.daniweb.com/techtalkforums/thread77189.html

Which zones are you hosting internally? Is there an external record pointing to the intended machine? Have you tried using conditional forwarders?
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You should be fine to add another account temporarily in Outlook 2003 (unless of course she won't let you!). Open the tools menu, choose Email Accounts, then view or change email accounts and from...

Yes Mikester :)

1. Remove the SVC, Host and/or PTR Records for the formerly internal resource on the machine hosting the primary zone.

2. Clear DNS cache of the machine hosting the primary...