Save Sent Emails in Shared Mailbox Sent Items folder

In this blog post, I will show you how to save sent emails in shared mailbox sent items folder. When you send email from a shared mailbox, the message isn’t saved in the shared mailbox’s Sent Items folder; instead, it’s saved in the sender’s Sent Items folder. This is the default behavior in Microsoft 365/Outlook.

We will explore different ways to resolve this issue and ensure that messages sent from a shared mailbox are saved in both the shared mailbox’s Sent Items folder and your own. In Microsoft 365 and Exchange Server (CU9 or later), new PowerShell cmdlets and flags are available to manage this setting. Let’s take a look:

Option 1: Configure Using Microsoft 365 admin center

You can use Microsoft 365 admin center to configure the shared mailbox so that messages sent from it are saved in its Sent Items folder.

• Sign in to the Microsoft 365 admin center > Expand Teams & groups > Shared mailboxes.
• Click on the Shared Mailbox.

• Click on Edit under Sent Items.

• Select Copy items sent as this mailbox for emails Sent As shared mailbox.

You can also optionally select Copy items sent on behalf of this mailbox for emails Sent on behalf of the shared mailbox.

Option 2: Configure Using PowerShell

You can use PowerShell to configure a shared mailbox to save sent messages to its own Sent Items folder. Use the Set-Mailbox cmdlet to enable this setting.

Steps for Microsoft 365/Exchange Server 2013 CU9 or later

• Launch PowerShell console as an administrator and execute the following commands.

Install ExchangeOnlineManagement PowerShell Module [Installation Guide]

Install-module ExchangeOnlinemanagement

Connect to Exchange Online

Connect-ExchangeOnline

For emails Sent As the Shared Mailbox (For a specific mailbox)

set-mailbox <mailbox-name> -MessageCopyForSentAsEnabled $True

For emails Sent As the Shared Mailbox [Apply to All Shared Mailboxes]

Get-Mailbox -ResultSize unlimited -Filter {(RecipientTypeDetails -eq 'SharedMailbox')} | set-mailbox -MessageCopyForSentAsEnabled $True

• If you have sent an email on behalf of a shared mailbox, you need to also set the -MessageCopyForSendOnBehalfEnabled flag to $true.

For emails Sent On Behalf of the Shared Mailbox (For one user)

set-mailbox <mailbox-name> -MessageCopyForSendOnBehalfEnabled $True

For emails Sent On Behalf of the Shared Mailbox [All Shared Mailboxes]

Get-Mailbox -ResultSize unlimited -Filter {(RecipientTypeDetails -eq 'SharedMailbox')} | set-mailbox -MessageCopyForSendOnBehalfEnabled $True

Steps for Exchange Server 2010

With the introduction of Update Roll-up pack 4 for Exchange Server 2010 Service Pack 2, an Exchange PowerShell cmdlet called Set-MailboxSentItemsConfiguration was introduced to configure the sent Items folder.

This configuration using Set-MailboxSentItemsConfiguration is a server-side feature, allowing Outlook to be configured in either Online mode or Cached mode. However, please be aware that in order to use this feature, the DelegateSentItemsStyle registry value must be disabled for Outlook.

To save Sent As emails in the Sent Items folder of both the sender and the shared mailbox, use the following command:

Emails sent from a Shared Mailbox with Send As permission

Set-MailboxSentItemsConfiguration -Identity "<shared Mailbox>" -SendAsItemsCopiedTo SenderAndFrom

To save Send As and Sent on Behalf permission emails in the Sent Items folder of both the sender and the shared mailbox, use the following command:

Emails sent from a Shared Mailbox with Sent on behalf and Send As permission

Set-MailboxSentItemsConfiguration -Identity "<shared Mailbox>" -SendAsItemsCopiedTo SenderAndFrom -SendOnBehalfOfItemsCopiedTo SenderAndFrom

Option 3: Configure using DelegateSentItemsStyle Registry key

For Outlook 2013 and later versions, you can follow below steps to configure DelegateSentItemsStyle registry key.

Outlook must be configured in cached mode for DelegateSentItemsStyle registry value to work correctly.

Note

• Press Win + R keys to open the Run dialog box.
• Type regedit and press Enter to open Registry Editor.
• Navigate to HKEY_CURRENT_USER\Software\Microsoft\Office\x.0\Outlook\Preferences registry key (The x.0 placeholder represents version of Office (16.0 = Office 2016, 15.0 = Office 2013, 14.0 = Office 2010).
• Create a new DWORD registry entry name DelegateSentItemsStyle and set its value to 1.
• Click on OK and Exit Registry Editor.

DelegateSentItemsStyle	MessageCopyForSentAsEnabled	Copy of the email will be saved in
0	True	Sender’s Mailbox = Yes Shared Mailbox = Yes
1	True	Sender’s Mailbox = No Shared Mailbox = Yes [2 copies of the email will be saved in Shared Mailbox] Sender’s Mailbox
0	False	Sender’s Mailbox = Yes Shared Mailbox = No
1	False	Sender’s Mailbox = No Shared Mailbox = Yes