A maximum of 2,000 mailboxes can be migrated to Office 365 by using a cutover Exchange migration. However, it is recommended that you only migrate 150 mailboxes.
What can’t be migrated
*mailboxes, mail users, mail contacts, and mail-enabled groups.
*Move\Migrate batch by workgroup so that it won’t break any delegate and delegates relationship access
Connect to Exchange Online Session
> Run the following commands
|$Creds = Get-Credential|
– credential of OnPremise admin
|Test-MigrationServerAvailability -ExchangeOutlookAnywhere -EmailAddress <firstname.lastname@example.org> -ExchangeServer <servername.domain.com> -Credentials $Creds -RPCProxyServer <owaurl.domain.com> -Authentication Basic|
– EmailAddress = email address of any account you are going to migrate with same domain
– Exchange Server = the name of the Exchange Server. Check it by opening the Exchange Server > This PC or My Computer> Right click and check the FULL COMPUTER NAME
– RPCProxyServer = their OWA url without https. (Ex. mail.domain.com)
If the result is Success proceed on number 2.
Should you have one, click here