How to update a sent item which was sent as another user? – Exclaimer Cloud

Scenario

You have Send-As permissions that allow you to send messages to another user from a shared mailbox. Although a signature is added to the outgoing email, but when you view the sent message in the Sent Items folder, you notice the signature is not present on the email.

Reason

Exclaimer uses a Sent Items Update feature to store sent messages (in your Sent Items folder) exactly as they were received, that is, showing the message and the appropriate signature that was applied (after the signature/mail disclaimer policies were applied).

The Sent Items Update feature can be configured to:

Only store sent items with signatures applied

OR
Store the original messages AND a copy of those messages with signatures applied

NOTE: When you send a message from a shared mailbox, that message is saved in YOUR Sent Items folder (NOT on the Sent Items folder associated with the shared mailbox).

No information about the sender is passed along with the sent message when using the Send As option; this means that Exclaimer cannot identify who's Sent Items folder the message has been saved to, so the message cannot be updated using Sent Items Update.

Resolution

To resolve this issue, you can change the mailbox to which items sent from a shared mailbox are saved.

To change the settings and place sent items in the associated Sent-As mailbox, you can follow any one of the options described below:

Option 1: Set a registry value on the Outlook client to allow users to make the change themselves.

This needs to be completed per user (that is, for anyone using the Send-As option). It ensures that the sent items are placed in the associated Sent-As mailbox instead of the sending user's Sent Items. This method requires Outlook to run in cached mode. To change which Sent Items folder is used, set the DelegateSentItemsStyle registry value on the Outlook client.

WARNING! Windows Registry modifications should always be approached with extreme care - serious problems can occur if you modify the Windows registry incorrectly! We strongly advise you to back up the Windows registry before any modifications are made - in doing so, you will have the option to restore the backup if a problem occurs. For more information, see How to back up and restore the registry in Windows.

NOTE: Outlook must be configured to run in a cached mode for this option to work correctly.

To update the Windows registry:

Launch the RegEdit (Registry Editor).
Browse to the following registry subkey:

HKey_Current_User > Software > Microsoft > Office > x.0 > Outlook > Preferences
Where, x.0 represents your Office version (example: 16.0 is Office 2016, 15.0 is Office 2013, 14.0 is Office 2010).
From the Edit menu, select New then select DWORD (32-bit) Value.
Enter the DWORD name as DelegateSentItemsStyle and press [Enter].
To edit the value, you can either right-click the DelegateSentItemsStyle and select Modify or double-click DelegateSentItemsStyle.

The Edit DWORD (32-bit) Value window is displayed.
In the Value data box, type 1.
Click OK to save the changes and close the window.
Restart Outlook for the change to take effect.

Option 2: Configure the mailbox to save a copy of the message to the Sent Items folder of the shared mailbox for an on-premises Exchange Server.

This method allows an Administrator to apply the setting to the mailbox; this means that anyone using the Send-As option for that mailbox will have a copy of the sent item placed in their own Sent Items folder AND a copy will be placed in the associated Sent-As mailbox. This method does not require Outlook to run in cached mode, and it updates both the Sent Items folder.

CAUTION!
You can configure the mailbox only on the following:

- Exchange 2010 Service Pack (SP) 3 and above

- Exchange 2013 Cumulative Update (CU) 9 and above

- Exchange 2016

To configure the mailbox, you need to:

Run the commands

See below for more information on how you can:

Install the Exchange Online PowerShell module

Connect to Exchange Online

To complete the steps described below, you will need:
Office 365 Global Administrator credentials

To run the commands:

For Exchange 2010 SP3 and above, open Exchange Management Shell, then run this command:

Set-MailboxSentItemsConfiguration <mailbox id> -SendAsItemsCopiedTo SenderAndFrom
For Exchange 2013 CU9 and above, Exchange 2016, Exchange 2019, open Exchange Management Shell, then run this command:

set-mailbox <mailbox id> -MessageCopyForSentAsEnabled $True

NOTE: If you have installed Exchange and run PrepareAD (Active Directory) using media for CU8 or earlier, you will need to manually run PrepareAD again using the CU9 and above media.

For more information, see Prepare Active Directory and domains for Exchange Server.

To Install the Exchange Online PowerShell V2 module:

Open the Windows PowerShell and run this command as an Administrator:

Install-Module -Name ExchangeOnlineManagement
Confirm that you want to install this PowerShell module.

Note: For additional installation options, see ExchangeOnlineManagement.

To connect to Exchange Online:

If you have Multi-Factor Authentication enabled, run this command:

Connect-ExchangeOnline -UserPrincipalName <UPN> -ShowProgress $true

In <UPN>, enter your username.

If you don't have Multi-Factor Authentication enabled, run this command:

Connect-ExchangeOnline -Credential $UserCredential -ShowProgress $true

When prompted, enter your password (and the Multi-Factor Authentication verification code if required).