When you view an appointment in Microsoft Outlook Web App for a recurring meeting and the meeting occurrence is canceled by its organizer in a Microsoft Exchange Server 2013 environment, the organizer's LegacyExchangeDN attribute instead of his or her name is displayed in the appointment. The appointment that contains the LegacyExchangeDN attribute looks something like this:
/O=CONTOSO/OU=EXCHANGE ADMINISTRATIV GROUP (XXXXXXXXXXXXXXX)/CN=RECIPIENTS/CN=UserName
However, the expected appointment for the organizer should look like:
Note There's no issue with the meeting request itself. The issue is related to the way of displaying the organizer's name.
This issue occurs because Exchange Server 2013 sets the LegacyExchangeDN attribute for the mismatching or not-presenting organizer property in a meeting appointment.