Exchange server source connection opens the wizard to configure the migration job. There you need to choose 'Connect using Global Admin User' and select the mailbox-type as 'Connect to Archive Mailbox (In-Place Archive)' then click 'Next'.
Choose 'Use Default connection' and enter the required login credentials to access the source Exchange server mailboxes.
You can select any one of the options to load the mailboxes
a. Load Mailboxes automatically
b. Load Mailboxes Using .CSV file
c. Load Mailboxes from previously stored list
Load Mailboxes automatically
It automatically loads all your mailboxes, if you are missing any mailbox then you can load the mailboxes using .CSV file.
Load Mailboxes Using .CSV file:
If you have chosen Load Mailboxes Using .CSV file, then you need to follow the below steps to load the mailboxes from CSV file.
Load Mailboxes from previously stored list
If you choose to Load Mailboxes from previously Stored List then it will display the already stored mailboxes.
Advantage
Using Global Admin Account for migration, lets you to use the single Global Admin account to migrate any Exchange server mailboxes and there is no need to login to each and every user for its migration.