How to update a sent item which was sent as another user in Signature Manager Exchange Edition


You send messages from a shared mailbox - you have Send-As permissions and send the message from another user. A signature is added (via Signature Manager Exchange Edition) to the outgoing email, but when you view the sent message in the Sent Items folder, no signature is present.


Signature Manager Exchange Edition uses a Sent Items Update feature to store sent messages (in your Sent Items folder) exactly as they were received - i.e. showing the message and the appropriate signature that was applied after signature/mail disclaimer policies were applied. The Sent Items Update feature can be configured to:

  • Only store sent items with signatures applied

  • -or-

  • Store your original message AND a copy of that message with signatures applied

However, when you send a message from a shared mailbox, that message is saved in YOUR Sent Items folder, not 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.


You can change the mailbox that items sent from a shared mailbox are saved to. Use one of the methods below to change settings and place sent items in the associated Sent-As mailbox:

  • Method 1: Set a registry value on the Outlook client
    This method allows users to make the change themselves, and needs to be completed per user (i.e. for anyone using the Send-As option). It ensures that sent items are placed in the associated Sent-As mailbox, instead of the sending user's Sent Items. This method requires Outlook to be running in cached mode.

Method 1: Set a registry value on the Outlook client

In this method, you set the DelegateSentItemsStyle registry value on the Outlook client, to change which Sent Items folder is used.

Windows Registry modifications should always be approached with extreme care - serious problems might 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 further information about how to back up and restore the Windows registry, see Microsoft KB Article 322756 : How to back up and restore the registry in Windows in the Microsoft Knowledge Base.

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

To update the Windows registry:

  1. Access the registry editor (start > run > regedit).

  2. Locate and then click the following registry subkey:

    HKey_Current_User > Software > Microsoft > Office > x.0 > Outlook > Preferences

    Where the x.0 placeholder represents your version of Office (16.0 is Office 2016, 15.0 is Office 2013, 14.0 is Office 2010).

  3. From the Edit menu, New > DWORD Value.

  4. Type DelegateSentItemsStyle and press Enter.

  5. Right-click DelegateSentItemsStyle and select Modify.

  6. In the Value data box, type 1.

  7. Click OK.

  8. Exit Registry Editor.

Method 2: Configure the mailbox to save a copy of the message to the Sent Items folder of the shared mailbox in Exchange Online or in on-premises Exchange Server (Updates both sent items folders). This method can only be used on Exchange 2010 SP3 and above, Exchange 2013 CU9 and above, or Exchange 2016.

  1. Run the Exchange Management Shell.
  2. Run the following command:

Exchange 2010 SP3+

  1. Set-MailboxSentItemsConfiguration <mailbox id> -SendAsItemsCopiedTo SenderAndFrom

Exchange 2013 CU9+ and Exchange 2016.

  1. set-mailbox <mailbox id> -MessageCopyForSentAsEnabled $True

Note: If you have installed Exchange, and run PrepareAD using media for CU8 or earlier, you will need to manually run PrepareAD again using the CU9+ media. Further details about running PrepareAD are available from Microsoft here.

Signature Manager Exchange Edition How To