During a public folder migration or when attempting to access public folders in Exchange, the following error may appear:

"There are no public folder servers available."

This error typically occurs when no public folder mailbox exists in the environment. Public folders require at least one public folder mailbox to be present and active. Without it, Exchange cannot mount or access the public folder hierarchy, resulting in this error.

This error can occur at both source and target during a migration.




 

Resolution

To resolve this issue, create a new public folder mailbox and then a root public folder.

For Exchange On-Premises:

Steps to Resolve

  1. Log in to the Exchange Admin Center (EAC).
  2. In the left navigation pane, go to Public folders.


     
  3. Click on Public folder mailboxes, then select + (Add) to create a new public folder mailbox.


     
  4. After the mailbox is created, go to Public folders.
  5. Click + (Add) to create a new root public folder.


     

For Microsoft 365:
Steps to Resolve

  1. Log in to the Exchange Admin Center (EAC).
  2. In the left navigation pane, select Public folders.


     
  3. Click Public folder mailboxes.
  4. Click + (Add) to create a Public Folder Mailbox.


     
  5. Then go to Public folders, and click + (Add) to create a root public folder.


     

Conclusion

After completing the steps above and successfully creating a public folder mailbox and root folder, the error "There are no public folder servers available" should no longer occur. You can now proceed with migrating your public folders without issue.