While migrating your groups, you noticed the following error in the logs: “Fatal error during migration process: Initialization of Office 365 Unified [Name of your group] […] Access Denied .”
The platform can not connect to your target Office 365 admin account.
Please check if the admin credentials, configured in your target connector, are correct.
Then restart your migration.
Note, that the platform doesn’t support ADFS/SSO authentication and 2-step verification. Deactivate these options before you start your migration.