The Configure legacy on-premises public folders for a hybrid deployment article explains how to configure legacy On-Premises Public Folders for a hybrid deployment.
This is useful in the following scenarios:
- Configuring a hybrid deployment for Microsoft 365 for a temporary reason, and the hybrid configuration will be rolled back at a later date.
- Migration of legacy Public Folders, with a plan to maintain a hybrid environment.
Follow the directions in the above linked TechNet article and complete step 4, where you run this command:
Set-OrganizationConfig -PublicFoldersEnabled Remote -RemotePublicFolderMailboxes PFMailbox1,PFMailbox2,PFMailbox3
- "Send As" permissions will not work in this scenario. A workaround is to set up a shared mailbox On-Premises, and then use this shared mailbox as the mailbox for "Send As" permissions.
- If migrating the On-Premises Public Folders to Microsoft 365, configure the admin account to look at Microsoft 365 folders by default, while all other users look at On-Premises Public Folders.
Here is a more detailed description of why this is needed:
- After running the PowerShell script in Step 4 of the TechNet article, the script will configure the organization on Microsoft 365 to use On-Premises Public Folders. By specifying the remote Public Folder mailboxes, the "DefaultPublicFolderMailbox" parameter will be configured on all user mailboxes on Microsoft 365, including the account used for the MigrationWiz migration. If that parameter is configured for the account performing the migration, each time a migration is performed, there will be an error stating that "no Public Folder mailbox was found on the Destination."
Here is an example script to change the DefaultPublicFoldermailbox parameter for the MigrationWiz account:
Set-mailbox –identity firstname.lastname@example.org –defaultpublicfoldermailbox 365PFMBX
- Change the identity to match the migration account, and change the defaultpublicfoldermailbox to match the Microsoft 365 default Public Folder mailbox.