Migrating Emails from another IMAP-Enabled Email System
Use of IMAP i.e. Internet Message Active Protocol for migration of user emails from Gmail and other email system is quite efficient. Any email system, which supports IMAP, can be migrated to the Office 365.
Through IMAP Migration, only inbox and other mail folders are migrated to the Office 365. IMAP cannot make use for migrating other items like contacts, calendar items and tasks. However, a user can migrate these items to the Office 365.
Another important thing to be noticed is inability to create mailbox in Office 365 with IMAP migration. You will need creating a mailbox for every user before migrating the emails. After the process of email migration is done, any new mail sent to the source email isn’t migrated.