Hi,

I'm having issues with duplicate items in the "sent" folder for two shared mailboxes. These items are only sent once, but appear twice in "sent".

The issue occurs in both OWA and Outlook clients, no matter which user sends the e-mail. The issue is only present on two shared mailboxes.

All previous TechNet threads regarding the same issue were because of IMAP settings, but this is Exchange.

Any ideas on what can cause this?

Regards

Erik Str

Does the emails appear on every Outlook client? - you could try to disconnect and reconnect the mailbox from a user - just to determine whether this is an indexing issue or if the emails are actually there.

Hi Erik Strlberg,

Few questions:

1. Is it a O365 or On-premises
2. If On-prem which CU.
3. Is it  Get-Mailbox -Shared or regular User mailbox used as a Shared mailbox. 

Below is something that is upcoming for On-Prem CU9:

This feature is designed to retain a copy of an email sent from the shared mailbox in the Sent Items folder of the shared mailbox.

A copy of the sent mail will also reside in the Sent Items folder of the members personal mailbox.

Sent Items when using shared mailboxes

Below is for Exchange 2010, you can check if it works for you.

Set-MailboxSentItemsConfiguration "Customer Support Feedback" -SendAsItemsCopiedTo SenderAndFrom

Few more findings:

EWS-based application

Email sent using Outlook are not saved to the Sent Items folder

Yeah they're visible on all clients as well as through OWA.

Hi,

On-prem, Exchange 2010 CU9. There was no option to select Exchange 2010 when I started th thread.

The mailboxes in question were created as shared mailboxes, they are not regular user mailboxes.

They only recently started displaying this behavior, they haven't done this in the past.

The configuration for MailboxSentItemsConfiguration is as follows:
SendAsItemsCopiedTo         : SenderAndFrom
SendOnBehalfOfItemsCopiedTo : SenderAndFrom
Identity                    : corp.lkab.com/CorpExchange/SM/SE SM Besk FK Krn
IsValid                     : True

SendAsItemsCopiedTo         : SenderAndFrom
SendOnBehalfOfItemsCopiedTo : SenderAndFrom
Identity                    : corp.lkab.com/CorpExchange/SM/SE SM Wassara Order
IsValid                     : True

Hi Erik,

Can you test if this happens when any member of the shared mailbox send email as the shared mailbox or from specific user's Outlook only.

Which is their primary profile, usermailbox or the shared mailbox.

Hi,

This happens for all members, including myself when I send test e-mails. It happens in Outlook and in OWA.

The primary user profile is the user mailbox, for all members.

Regards

Erik Strlberg

Hi Erik,

Now test these two things.

1. When you are sending email as some non-problematic shared mailbox. Do you see an email in the Sent Item of the shared mailbox as well as in your Personal-Sent Items as well.
2. What do you see if you send email from a problematic shared mailbox, do you still see the user(actual sender) copy.
   
   

• Run the Get-MailboxSentItemsConfiguration against the working shared mailboxes and let me know if the settings are same.
• Check if your Outlook is configured to be running in Cached Mode. If yes try switching to Online and see if still the issue re-occurs.
  
• Is DelegateSentItemsStyle registry key present or set with a value.
  

Key: HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Preferences
Name: DelegateSentItemsStyle

Also on the problematic shared mailbox, change the settings as below and let me know the results.

Set-MailboxSentItemsConfiguration SharedMBX1 -SendAsItemsCopiedTo Sender		

Hi,

1. Yes, both the shared mailbox and my personal "sent" folders get copies of the sent item.

2. Yes, even on the problematic boxes both the user and the shared mailbox get the sent items.

All settings on Get-MailboxSentItemsConfiguration are the same on the problem mailboxes and the working mailboxes.

I'm running online mode, other users who are experiencing the same problem are running cached mode.

DelegateSentItemsStyle is 0 on all clients, but the issue occurs on OWA as well so it shouldn't be client related.

I changed SendAsItemsCopiedTo to "Sender", same issue.

Regards,

Hi Erik,

If you have set the SendAsItemsCopiedTo to "Sender", and still the user and shared mailbox sent items gets a copy, it will be a problem with the mailboxes (maybe corrupted in some sort)

Try repairing them using New-MailboxRepairRequest, various parameters.

Eg.

New-MailboxRepairRequest -Mailbox shared1@contoso.com -CorruptionType FolderView 

Hope this issue is not concentrated around a single DB.

If doesn't help you might consider moving the data out to a PST and creating new shared mailboxes for them.

Hi,

I've tried New-MailboxRepairRequest but the problem still persists. I think the only thing left to do is recreating the shared mailbox.

Thanks for your help!