Office 365 Shared Mailbox Sent Items Limitation

Office 365 Shared mailbox makes it easy for a specific group of people to monitor and send email from a common email address. When a person in the group replies to a message sent to the shared mailbox, the email appears to be from the shared mailbox not from the individual user. Shared Mailbox sent items limitation that cause compliance / regulatory issues for most of the customers utilizing shared mailbox is fixed now. Microosft has fixed this issue for all the customers and now customer can leverage the use of Shared Mailbox in Office 365 and on prem version of Exchange. Before we look at the resolution let’s have a look at shared mailbox sent items issue.

When a user sends an email using shared mailbox alias, the email goes directly to the sent items of sender instead of shared mailbox sent item. This is something that cause issues for organizations using Shared Mailboxes. To meet the compliance requirements organizations need control over Shared Mailbox sent items and admin don’t have to runMailbox Audit logging to nail down the sender of email.

Shared mailboxes are a great way to handle customer email queries because several people in your organization can share the responsibility of monitoring the mailbox and responding to queries. Your customer queries get quicker answers and related emails are stored in one mailbox. A shared mailbox doesn’t have its own user nameand password.

Microsoft didn’t have any control over shared mailbox sent items in Exchange 2013 and Exchange online and as a fix customer need to make registry changes on end users machine. This cause a lot of administrative overhead for customers and IT admins. Several customers of mine has not considered to upgrade to Exchange 2013 or migrate to Office 365 due to this limitation of sent items.

Registry fix doesn’t work with the users using outlook in online mode. This fix is only applicable when user is running outlook in cached mode.

With Exchange 2013 CU9 email sent by a user using shared mailbox will be delivered to the Sent Items folder of shared mailbox and to the user mailbox sent items. Microsoft has already started to roll out this new feature to the customers using Office 365 shared mailboxes.

Enable Office 365 Shared Mailbox Sent Items Feature

By default, this feature will be disabled to all the customers and administrator need to run the following PowerShell cmdlet.

For emails Sent As the shared mailbox: Set-mailbox <mailbox name> -MessageCopyForSentAsEnabled $True

For emails Sent On Behalf of the shared mailbox: Set-mailbox <mailbox name> -MessageCopyForSendOnBehalfEnabled $True

Disable Office 365 Shared Mailbox Sent Items Feature

To disable this feature run the following powershell cmdlets

For emails Sent As the shared mailbox: Set-mailbox <mailbox name> -MessageCopyForSentAsEnabled $False

For emails Sent On Behalf of the shared mailbox: Set-mailbox <mailbox name> -MessageCopyForSendOnBehalfEnabled $False

To enable this feature for Exchange online, we need to first connect to Exchange online powershell.

More information on new enhancements in exchange 2013 CU9 can be found on Microsoft Knowledge Base.