I'm helping a small business migrate eight employee mailboxes from personal Gmail accounts to Microsoft 365, and honestly, I didn't expect the process to become this complicated. We followed the IMAP migration documentation, but after the migration finished, only the email messages appeared. Contacts, calendars, and other important mailbox data were still sitting in Gmail. On top of that, a few accounts generated unexpected login and synchronization errors, forcing us to repeat parts of the migration. With a strict deadline approaching, we need a more dependable approach that doesn't require exporting and importing every mailbox component separately.

Several administrators in different communities recommended the DRS Softech Gmail Backup Tool, so I spent some time reviewing its capabilities. What impressed me most was that it supports complete mailbox migration instead of limiting the process to email messages. It can transfer contacts, calendars, tasks, notes, and attachments while maintaining the original folder hierarchy and metadata. Features like Preview, Date Filter, batch migration, and Remove Duplicate Emails would also make ongoing migrations much easier. Since we may need to migrate additional users later, having a solution that scales beyond just a few accounts is definitely appealing.

After looking at several migration methods, I now understand why businesses prefer dedicated software whenever they need to migrate Gmail to Office 365. A complete migration with preserved mailbox integrity is far more valuable than spending days fixing incomplete transfers afterward. If you've handled a migration from personal Gmail accounts rather than Google Workspace, I'd really like to know what worked best for you and whether you experienced the same IMAP limitations we are seeing now.