Get-Mailbox -ResultSize Unlimited | Add-MailboxPermission -AccessRights FullAccess -User MigrationWiz
Some Hosted Exchange providers allow this access to be granted via their web portal. In this case, you could log in to each mailbox via their portal, and grant the migration account (e.g., "MigrationWiz") to have read/write access to each mailbox. Obviously this is laborious and time-consuming, and so it is preferable that the Hosted Exchange provider run the PowerShell script above, particularly if you have a large number of users.
New-ManagementRoleAssignment -Role ApplicationImpersonation -User <admin_user_name>
Options to obtain these:
For the Source endpoint:
Watch this video to see a walk-through of the steps below.
Create the Mailbox Migration project. KB004380
Add the accounts (also referred to as "items") that will be migrated to the project. Use the Bulk Add option, and then import from the CSV file that you prepared when following the steps under Prerequisites section of this guide. KB004842.
Reconfigure Outlook profiles to use Amazon WorkMail. For more information, see Connect Microsoft Outlook to Your Amazon WorkMail Account. Note: Users must create new Outlook profiles, and set up their signatures again, and reattach any PST files that were attached to their previous profile.
Set up Amazon WorkMail on your Kindle, Android, iPad, iPhone, or Windows Phone. For more information, see Connect Your iOS Device and Connect Your Android Device.