To back up all data of an Office 365 group, the Global admin service account used for the backup must be a member of the group. For non-dynamic groups, Keepit automatically makes the Global admin a member. However, since a dynamic group differs from other Office 365 groups in that it uses rules to determine group membership, Keepit is unable to make the Global admin a member. This means that you must make sure that the Global admin meets all the membership rules that are applied to the group so that it becomes a member. This will ensure that all dynamic group data is backed up including files, team sites, conversations, calendars, plans, and channels conversations. 

If the Global admin is not a member, then the following will be backed up:

  • If the dynamic group is public and the Global admin is neither a member nor owner, all data types except for plans will be backed up.
  • If the dynamic group is private and the Global admin is neither a member nor owner, only files and team sites will be backed up.
  • If the dynamic group is public or private and the Global admin is an owner but not a member, all data types except for plans will be backed up.

For more about dynamic groups, please refer to Microsoft's documentation: https://docs.microsoft.com/en-us/azure/active-directory/users-groups-roles/groups-dynamic-membership

Note: When you restore a dynamic group, it will become an Office 365 group with assigned membership.