When you use a program that is written to use CDO version 1.2 to modify a meeting, the meeting organizer is included as a required attendee

You use a program that is written to use Collaboration Data Objects (CDO) version 1.21 with Cdo.dll. When you use this program to modify a meeting and to send a meeting update, the update message is sent to all required attendees. Sometimes, the meeting organizer is included as a required attendee.

The meeting organizer is added to the recipients list for the meeting with a flag that indicates that this user is the meeting organizer. Microsoft Outlook uses this flag to prevent update messages from being sent to the meeting organizer. However, Cdo.dll does not use this flag.

To resolve this issue, use one of the updated versions of Cdo.dll that are described in this section. These versions will prevent update messages from being sent to the meeting organizer.

Microsoft Exchange Server 5.5

This issue was resolved in the version of Cdo.dll that is included in the software update that is described in the following Microsoft Knowledge Base article:

Microsoft Exchange 2000 Server and Microsoft Exchange Server 2003

This issue was resolved in the version of Cdo.dll that is included in Exchange Server 2003.

There are no plans to release an updated version of Cdo.dll for Exchange 2000. For Exchange 2000 environments that have servers that are running programs that use Cdo.dll to modify a meeting, we recommend that you update the version of Cdo.dll on these servers to the version of Cdo.dll that is included in Exchange Server 2003.