Behavior of Meeting Forward Notifications

Mrs. Proactive said “I had tough time finding any information on the behavior of Meeting Forward Notifications so I thought I would share what I found.” Don’t we all appreciate her sharing some wisdom with us? Here it is:

Meeting Forward Notification (MFN) is processed by either the Exchange Calendar Assistant or Outlook and the organizer’s meeting is automatically updated to include the new attendee.  Now, when the organizer sends out a meeting update, the new attendee gets the update too.

When a meeting is forwarded by one of the attendees using Outlook 2010, several things happen:

  • Outlook displays an InfoBar message to let the attendee know that a MFN will be sent to the meeting organizer.
  • Outlook forwards the meeting to the new attendee.
  • A meeting forward notification is sent to the meeting organizer (in most situations).

Depending on the client of the organizer, the Exchange version of the attendee forwarding the meeting, and the organization membership of both parties, the meeting forward notification can either be sent by Exchange or Outlook, or neither product.

The following outlines a few scenarios where MFNs are sent by different sources, or not sent at all.

  • If the Organizer is using Outlook 2010

AND the attendee who forwarded the meeting is in the same Organization as the Organizer

AND the attendee is using Outlook 2010 in Exchange 2007 or Exchange 2010

THEN the MFN will be sent by Exchange

  • If the Organizer is using Outlook 2010

AND the attendee who forwarded the meeting is in the same Organization as the Organizer

AND the attendee is using Outlook 2010 in Exchange 2003

THEN the MFN will be will be sent by Outlook 2010

  • If the Organizer is using Outlook 2010

AND the attendee who forwarded the meeting is in a DIFFERENT Organization than the Organizer

AND the attendee is using Outlook 2010 in any version of Exchange

THEN the MFN will be will be sent by Outlook 2010

  • If the Organizer is using a non-Outlook client

AND the attendee is using Outlook 2010 in any version of Exchange

THEN the MFN will be will not be sent

If Outlook sends the MFN, you will find a copy of the MFN in the Sent Items folder of the attendee that forwarded the meeting.

However, if Exchange sends the MFN, the MFN is not in the Sent Items folder of the attendee forwarding the meeting.

There are some scenarios where a meeting forward notification is not sent by Outlook when the attendee forwards the meeting to another user.  In this situation, the InfoBar of the forwarded meeting does not include the text indicating a meeting forward will be sent.

Outlook makes the determination not to send the meeting forward notification by first analyzing the Global Object ID value of the meeting.  Outlook parses this value to see if the organizer is using an Outlook client. 

Depending on the version of Exchange hosting the mailbox for the meeting organizer, the organizer’s experience varies slightly.

Mailbox hosted on Exchange 2007 (or later)

If the organizer’s mailbox is on Exchange 2007 or Exchange 2010, they will see the best experience because the Exchange Calendar Assistant processes the meeting forward notification. When the Calendar Assistant processes the MFN, the following events take place:

  • The organizer’s meeting is updated to include the user to which the meeting was forwarded by the attendee.
  • Meeting exceptions are created for recurring meetings where the user was forwarded only one instance in the series.

In this example, Exchange 2007 User2 is the meeting organizer and Exchange 2007 User3 is the meeting attendee that forwarded the meeting request to Exchange 2007 User4. With Exchange Store tracing enabled, you can see the Calendar Assistant processes the meeting forward notification and updates the organizer’s meeting to include the new attendee.

Now, when the meeting organizer opens the meeting on their calendar, the new user is automatically included in any meeting updates sent by the organizer.

This keeps all relevant attendees up-to-date on the meeting.  In earlier versions of Outlook, the user to which the meeting was forwarded usually is not included on the organizer’s calendar item.

Mailbox hosted on Exchange 2003 or non-Exchange mailbox

The Calendar Assistant does not exist for an Exchange 2003 mailbox. Therefore, the meeting forward notification is processed by Outlook. This can occur during any of the following events:

  • The sniffer process is called when the MFN is processed by the cached mode incoming item pipeline
  • MAPI-idle sniffer time
  • The organizer views the MFN in the Reading Pane
  • The organizer opens the MFN in the inspector window

When Outlook processes the MFN, the following events occur:

  • The organizer’s meeting is updated to include the user to which the meeting was forwarded by the attendee.

Meeting exceptions are created for recurring meetings where the user was forwarded only one instance in the series.

Out of date Meeting Forward Notifications

In some scenarios, the MFN received by the organizer is out-of-date.  When this occurs, the MFN includes a button that the organizer can use to send a meeting update to the attendee who was forwarded the out-of-date meeting invite.

Outlook uses the Sequence property value (0x813E0003) on the meeting to determine if the meeting forward notification is out of date.

When the organizer clicks Send Meeting Update, the meeting invitation includes the very latest details on the meeting.

This ensures the newly added attendee’s calendar is up-to-date.

Registry settings to manage the meeting forward notification features

There are two policy settings available to control the meeting forwarding notification features in Outlook 2010.

Prevent Outlook from sending a meeting forward notification:

Use the following registry data to control the sending of meeting forward notifications by Outlook 2010.

Key:  HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Options\Calendar

DWORD:  DisableOlkSendingMtgFwdNotifs

Values:

  0 (or missing DWORD) = Outlook sends an MFN (default)

  1 = Outlook does not send an MFN

Note: The DisableOlkSendingMtgFwdNotifs registry value is only used when Outlook is responsible for sending MFNs. If Exchange is responsible for sending the MFN, this registry value has no effect on Outlook. Also, there is no way to stop Exchange from sending an MFN.

Hide the Send Updated Meeting button

Use the following registry data to control the display of the Send Updated Meeting button in an out-of-date MFN viewed in the Reading Pane by the organizer.

Key:  HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Options\Calendar

DWORD:  HideSendLatestVersionButton

Values:

  0 (or missing DWORD) = Outlook shows the Send Updated Meeting button on an out-of-date meeting forward notification

  1 = Outlook does not show the Send Updated Meeting button on an out-of-date meeting forward notification

Wow, not only you are generous Mrs. Proactive, you can write. I am certain though that readers will appreciate your attention to details. Thanks!