Why do I get an error when I try to run the Public Folders mapping script?
For errors (as shown in the screen shots below) that state that the Public Folders are in 'HoldforMigration' mode when running the scripts received from BitTitan Support, the most likely reason for this is that Public Folders are being run in hybrid mode.
There are more details below, as well as the steps to resolve this to successfully run the scripts from Support. Once the scripts have completed, hybrid mode can be re-enabled. The steps to do this are also included below.
When planning to migrate legacy Public Folders to Office 365, carefully read the Public Folder migration guide.
If the total size of the On-Premises Public Folders is greater than 50GB, the Migration Guide references KB004924 that will provide the necessary steps to contact Support and request the Public Folders mapping script.
Support will then send two (2) scripts that should be run on the Exchange Online PowerShell:
If using the Public Folders in Hybrid Mode (more information in KB005102), if the Office 365 users are still using the On-Premises Public Folders, it is not possible to create the Public Folders in Office 365.
When running the script to create the mailboxes, there will be a warning stating that the newly created Public Folder mailboxes were automatically put on hold for migration, due to the fact that the Office 365 Organization has the Public Folders configured as "Remote".
When you try to run the script that creates the Public Folders, you will see the following error:
All of the Public Folder mailboxes created were put in a 'HoldForMigration' state, and therefore it is not possible to create new Public Folders on Office 365.
This is caused by the fact that the Office 365 Organization has been configured to use the Public Folders in hybrid mode, so that users can access the On-Premises Public Folders.
Take a quick look at the root Public Folder mailbox, by running from the Exchange Online PowerShell: (Get-OrganizationConfig).rootpublicfoldermailbox |fl
The picture above shows that the root Public Folder mailbox is locked for migration. All other Public Folder mailboxes will also be unavailable. Now look at the Organization Configuration by running from the same PowerShell: Get-OrganizationConfig |fl *public*
The PublicFoldersEnabled attribute set to remote confirms that the Office 365 users are set to use the On-Premises Public Folders.
To resolve this issue, and to be able to run the scripts and create the Public Folders on Office 365:
This last change can take a while to apply. To make sure that the change applied, run the following cmdlet: Get-Mailbox <username> |fl *public*
Once you are certain that the default Public Folder mailbox is the one On-Premises, inform the users that the access to the Public Folders has been restored. Again, this might take up to one hour, so plan the Public Folders downtime carefully.
Finally, since the Organization Configuration on Office 365 has been changed, revisit the KB005102 and follow the instructions to make sure that the MigrationWiz administrator on Office 365 has an Office 365 Public Folder mailbox as default.