Splitting Public Folder Migrations When Migrating More Than 1,000 Folders

If migrating more then 1,000 public folders (including sub-folders), it is important to work with BitTitan Support so that the migration can be split up, based on migration points after every 1,000 folders.

Here are the steps to follow:

  1. Create a Public Folder migration project.
  2. Select the Source endpoint and enter admin credentials.
  3. Select the Destination endpoint and enter admin credentials.
  4. Submit a ticket to BitTitan Support, by following the directions in How do I get support for your products? In the ticket description notes, add the name of the Public Folder migration project, and specify that the Source Public Folders have more than 1000 folders. The title of ticket should include the following text: "Request to split Public Folder migrations based on child Public Folder count." In addition, run the following  PowerShell command in your Source Exchange Management Shell (EMS) or Source Microsoft 365 PowerShell environment and include the results of the command, by providing the folders.csv file, generated from running the script, to the ticket:

Get-PublicFolder -Recurse -Resultsize Unlimited | select Identity | Export-Csv -Encoding Unicode C:\folders.csv

BitTitan Support will then create a new MigrationWiz project on your behalf, and configure the new migration points as needed. 

Additionally, the split process will:

  • Create a new MigrationWiz project called (project)_SPLIT.
  • Create additional "migration points" in addition to the top-level folders already configured. These are created in Microsoft 365. The extra migration points will assist with processing the migration expeditiously.
  • Count the number of subfolders from the root, and then create a new migration point after every 1,000 folders from the top-level folder.
  • Configure folder filters. These are used to start and stop the migration points.


  • Any new folders created after the Public Folder split is initiated will not be in scope for the migration.
  • The original project will not be affected or changed, and will remain in your list of MigrationWiz projects. However, do not continue the Public Folder migration project from the original project.
  • Once the tool is complete, you should run the migration from the new project, and can then delete the original project.
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