IMAP to On-Premises Exchange Migration Guide
Get-Mailbox -ResultSize Unlimited | Add-MailboxPermission -AccessRights FullAccess -Automapping $false -User MigrationWiz
Verify mailbox accessibility, using EWS. KB004304
If you are using ISA to protect an Exchange Server, make sure that Exchange is published properly. KB004960
If you want to be able to migrate messages with attachments larger than 10MB, the following limits need to be increased:
For the Source endpoint:
Click on EndPoints > Add Endpoint > Enter endpoint name > For endpoint type select IMAP.
Server Name should follow format: imap.example.com
Enter server port. As a general rule, the server port will be either 143 or 993 (if using SSL). Note: If using SSL, checkmark the Use SSL box.
Enter the OWA URL KB004392
Click on the Provide Credentials radio button, and enter the admin account credentials for the account that was set up under the Prepare The Destination Environment of this guide.
Watch this video to see a walk-through of the steps below.
Create the Mailbox Migration project. KB004380
Source Password: Enter the administrator's password.
For the Destination, you only need to enter the Destination email address of each user.