A Public Folder migration could fail for a variety of reasons. The broad actions listed below can be used to solve a variety of issues that can come up while moving public folders.

Resolution:

Office 365 Public folders:

1. ​Log in to Microsoft 365 using admin account
2. Navigate to 'Exchange' under 'Admin centers'
3. Select the 'Public folder mailboxes'
4. Ensure that there is at least one Public Folder mailbox. If not, create a new for the Public Folders migration
5. Click the ‘Public folders’ in the left panel
6. Click '...' and choose 'Root Permissions'
7. Ensure that the admin user has owner permission. If it is not, add admin as owner and apply the change to all subfolders
8. Ensure that the admin user has Outlook. If not, assign the user the required Microsoft 365 license
9. By selecting the Outlook tab, make sure you can see the mailbox
10. Visit the 'Microsoft 365 Admin center' again
11. Select the 'Users' from the left panel
12. Choose the admin user, then check that:
    1. The admin user is in the active users list
    2. The admin user has a valid Microsoft 365 license
    3. The admin user name is spelled correctly

Exchange Public folders:

1. ​Log in to 'Outlook Web Access (OWA)'portal​ with the global admin account. If authentication fails, ensure that the user name and password are appropriate
2. Check that you can view the content of your mailbox
3. Verify that the admin account can access the migrated Public Folders and Public Folder mailboxes
4. Ensure that all Public Folders being migrated have owner permissions for the admin account