One of the more common questions we see is "Can we migrate Exchange without any trusts in the environment?"The answer to that is "YES" however there are some hurdles. Here are 3 of them:
To configure the Client Profile Updating Utility to process the Microsoft Outlook profiles if trust relationships are not established between the source and target domains, perform the following steps:
While we do recommend getting a trust in place, it's important to know the drawbacks to a trustless migration.