Create a public folder mailbox in Exchange Server

Before you can create a public folder in Exchange server, you must first create a public folder mailbox. Public folder mailboxes contain the hierarchy information as well as the content for public folders.

The first public folder mailbox that you create in the organization is the primary hierarchy mailbox, which contains the only writable copy of the public folder hierarchy. Any additional public folder mailboxes that you create are secondary hierarchy mailboxes, which contain a read-only copy of the public folder hierarchy. You can create multiple public folder mailboxes for load balancing.

Note

For more information about the storage quotas and limits for public folders in on-premises Exchange, see Limits for public folders.

For additional management tasks related to public folders in Exchange Server, see Public folder procedures.

What do you need to know before you begin?

Tip

Having problems? Ask for help in the Exchange forums. Visit the forums at: Exchange Server, Exchange Online, or Exchange Online Protection.

Use the EAC to create a public folder mailbox

  1. In the EAC, go to Public folders > Public folder mailboxes, and then click Add Add icon.

  2. In the New public folder mailbox page that opens, enter the following information:

    • Name: Enter the name for the public folder mailbox.

    • Organizational unit: Click Browse to select the location in Active Directory where the mailbox object is created.

    • Mailbox database: Click Browse to select the mailbox database where the mailbox is created.

    When you're finished, click Save.

Use the Exchange Management Shell to create a public folder mailbox

To create a public folder mailbox, use the following syntax:

New-Mailbox -PublicFolder -Name <Name>

This example creates the primary hierarchy public folder mailbox named Master Hierarchy, because this is the first public folder mailbox in the organization (the value of the Name parameter doesn't determine whether the mailbox is the primary hierarchy public folder mailbox).

New-Mailbox -PublicFolder -Name "Master Hierarchy"

This example creates a secondary hierarcy public folder mailbox named Istanbul, because this isn't the first public folder mailbox in the organization (the value of the Name parameter doesn't determine whether the mailbox is a secondary hierarchy public folder mailbox).

New-Mailbox -PublicFolder -Name Istanbul

For detailed syntax and parameter information, see New-Mailbox.

How do you know this worked?

To verify that you've successfully created the a public folder mailbox, do any of these steps:

  • In the EAC, go to Public folders > Public folder mailboxes and verify the public folder mailbox is listed. The primary hierarcy public folder mailbox has the value Primary Hierarchy for the Contains property. All other public folder mailboxes have the value Secondary Hierarchy for the Contains property.

  • In the Exchange Management Shell, run the following command to verify the mailbox is listed, and check the value of the IsRootPublicFolderMailbox property to see if the mailbox is the primary hierarchy public folder mailbox (True) or a secondary hierarchy public folder mailbox (False):

    Get-Mailbox -PublicFolder | Format-Table -Auto Name,ServerName,Database,IsRootPublicFolderMailbox
    
  • In the Exchange Management Shell, run the following commands to verify the primary hierarchy public folder mailbox:

    1. Run the following command:
    ```
    Get-OrganizationConfig | Format-List RootPublicFolderMailbox
    ```
    
    1. Use the GUID value returned by the first command with Get-Mailbox to confirm the mailbox name. You can copy the GUID value by right-clicking in the Exchange Management Shell window, selecting Mark, highlighting the GUID value, and then pressing ENTER.
    ```
    Get-Mailbox -PublicFolder -Identity <GUID>
    ```