Hello, 

So we have a weird problem tat we have being trying to diagnose for a while and I think that I have finally got to the bottom of the problem, just now need to find a solution.

We have a shared email email account. This is set up as shared mailbox in exchange (2010) with Full Control and Send On behalf of privileges given to three users. Each of these users has added this shared mailbox as a second account to their outlook (2010) profile.

The Problem we have appears to be two fold. For some reason emails are not sent immediately for this account even though this is value of the setting in outlook. This puts an email in the shared mailbox outbox. We then have a race condition where by the first user of the shared mailbox whose outlook client does a send an receive first becomes the user who sent the email on behalf of the shared inbox rather than the user that hit sent. This has caused mild confusion for the recipients as signatures of the email does not match what outlook is displaying.

So, firstly is this expected behaviour for shared accounts, that the outbox is shared so this race condition will always exists?Secondly, any idea why on this second mailbox attached to outlook emails are not always sent immediately? In fact this appears to be a bigger problem, email not getting sent until people hit send and receive has just happened to someone else. What can I do to diagnose this issue?

Cheers

Rich

Hi,

Based on the description above, the issue is that when you send an email message from a shared mailbox, the sent email message remains in your Outbox until you manually perform a Send/Receive operation.

As far as I know, this problem occurs when both the following conditions are true:

• Your Outlook profile is configured in online mode (not cached Exchange mode).
• You have the DelegateSentItemsStyle registry value set to 1.

If you are using Online Mode, please switch to Cached Exchange Mode to check the result, if the issue doesn't occur then, please note there is no resolution to this problem other than to either switch your profile to cached Exchange mode or set the DelegateSentItemsStyle registry value to zero (0). Additionally, if your mailbox is located on Microsoft Exchange Server 2010 (or later), the Exchange administrator can configure similar behavior on the server.

Important Follow the steps in this section carefully. Serious problems might occur if you modify the registry incorrectly. Before you modify it, back up the registry for restoration in case problems occur.

To change the value of DelegateSentItemsStyle to 0 in the registry, follow these steps:

1. Exit Outlook.
2. Start Registry Editor.
   
   In Windows 8 and Windows 8.1
   
   Swipe in from the right to open the charms, tap or click Search, and then type regedit.exe in the search box. Or, type regedit.exe at the Start screen, and then tap or click regedit in the search results.
   
   In Windows Vista and Windows 7
   
   Click Start, type regedit in the Start Search box, and then press Enter. If you are prompted for an administrator password or for confirmation, type the password, or click Allow.
   
   In Windows XP
   
   Click Start, click Run, type regedit, and then click OK.
3. Locate and then select the following registry key: HKEY_CURRENT_USER\Software\Microsoft\Office\<var>x</var>.0\Outlook\Preferences
   Note In this key path, the placeholder <var>x</var>.0represents 15.0 for Outlook 2013, 14.0 for Outlook 2010, 12.0 for Outlook 2007, and 11.0 for Outlook 2003.
4. Select the DelegateSentItemsStyle value.
5. On the Edit menu, click Modify.
6. Type 0, and then click OK.
7. Exit Registry Editor.
8. Start Outlook.

More details about the issue can be found in this kb below:

Email remains in the Outbox when you use the DelegateSentItemsStyle registry value

Regards,

Melon Chen
TechNet Community Su