If you are migrating from an existing Exchange Server environment the steps are relatively similar. As the Office 365 Small Businesses and Professionals plan does not allow Directory Synchronization we have limited the scope of this section to a cutover migration method.
The key steps involved in performing a migration from an on-premise Exchange Server are:
Ensure that remote connectivity is possible using RPC over HTTP (as discussed in Chapter 5, Preparing for a Simple Migration).
Grant the migration user full access to the mailboxes or mailbox store.
Run the Migration wizard from the Exchange Online control panel.
Assuming that you have successfully prepared your Exchange Server environment to allow RPC over HTTP and tested it using the Exchange Remote Connectivity Analyzer, we can now move towards the steps involved in migrating the mailboxes.
The first task required is to allow the migration administrator permissions...