Enable or disable MAPI for a mailbox

You can use the Exchange admin center or Exchange Online PowerShell to enable or disable MAPI for a user mailbox. When MAPI is enabled, a user's mailbox can be accessed by Outlook or other MAPI email clients. When MAPI is disabled, it can't be accessed by Outlook or other MAPI clients. However, the mailbox will continue to receive email messages, and, assuming that the mailbox is enabled to support access by those clients, a user can access the mailbox to send and receive email by using Outlook on the web (formerly known as Outlook Web App), a POP email client, or an IMAP client.

Note

Support for Outlook on the web and MAPI, POP3, and IMAP4 email clients is enabled by default when a user mailbox is created.

For additional management tasks related to managing email client access to a mailbox, see the following topics:

What do you need to know before you begin?

Tip

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

Use the new Exchange admin center to enable or disable MAPI

  1. In the new EAC, navigate to Recipients > Mailboxes.

  2. In the list of user mailboxes, click the mailbox that you want to enable or disable MAPI. A display pane is shown for the selected user mailbox.

  3. Under Mailbox settings > Email apps, click the Manage email apps settings link.

  4. In the Manage settings for email apps display pane, do one of the following.

    • To disable MAPI, for the Outlook desktop (MAPI) option, when the button is Enabled, set to Disabled.

    • To enable MAPI, for the Outlook desktop (MAPI) option, when the button is Disabled, set to Enabled.

  5. Click Save to save your change. A message Email app settings updated successfully is displayed. Click Close to exit.

Use the Classic EAC to enable or disable MAPI

  1. In the Classic EAC, navigate to Recipients > Mailboxes.

  2. In the list of user mailboxes, click the mailbox that you want to enable or disable MAPI, and then click Edit Edit icon..

  3. On the mailbox properties page, click Mailbox Features.

  4. Under Email Connectivity, do one of the following.

    • To disable MAPI, under MAPI: Enabled, click Disable.

      A warning appears asking if you're sure you want to disable MAPI. Click Yes.

    • To enable MAPI, under MAPI: Disabled, click Enable.

  5. Click Save to save your change.

How do you know this worked?

To verify that you've successfully enabled or disabled MAPI for a user mailbox, do one of the following:

  • In the EAC, navigate to Recipients > Mailboxes, click the mailbox, and then click Edit Edit icon..

  • On the mailbox properties page, click Mailbox Features.

  • Under Email Connectivity, verify whether MAPI is enabled or disabled.

Use Exchange Online PowerShell to enable or disable MAPI

This example disables MAPI for the mailbox of Ken Sanchez.

Set-CASMailbox -Identity "Ken Sanchez" -MAPIEnabled $false

This example enables MAPI for the mailbox of Esther Valle.

Set-CASMailbox -Identity "Esther Valle" -MAPIEnabled $true

For detailed syntax and parameter information, see Set-CASMailbox.

How do you know this worked?

To verify that you've successfully enabled or disabled MAPI for a user mailbox, do one of the following:

  • Run the following command in Exchange Online PowerShell.

    Get-CASMailbox -Identity <MailboxIdentity>