Customize your mailbox migrations by selecting to copy emails, calendars, contacts, and mailbox rules.

To access the Copy options, follow the steps in the Copy mailboxes overview article until you have selected your destination tenant.

Select what items you want to copy in your mailbox migration.

Copy the messages in your mailboxes.

Select the last 90 or 180 days or use custom dates from the dropdown.

Copy events created or modified by the mailbox owner.

If you choose to have new Teams meeting links at the destination, you will have two active meetings for the same event during the migration—the one from the source and the one created at the destination.

When you use that option, users could confuse the source and destination meeting invitations and miss the meeting.

While this should not cause a problem if you communicate the transition with your internal users, external attendees might miss some meetings if they don't understand why they received a second invitation.

Copy contacts in your mailboxes.

Copy rules in your mailboxes.