attConversationID and attParentID
Applies to: Outlook 2013 | Outlook 2016
The Windows for Workgroups 3.1 Mail conversation key is a text string. The MAPI equivalent is a binary value. To provide backward compatibility, the TNEF implementation converts the binary data to text and adds a terminating null character.
Note
The corresponding properties in MAPI to which these TNEF attributes are mapped, PR_CONVERSATION_KEY and PR_PARENT_KEY, have been deprecated in Microsoft Exchange Server: Use of PR_CONVERSATION_KEY, the PidTagConversationKey Canonical Property, persists in Outlook only, for locating IPM.MessageManager messages.
Remarks
The PR_CONVERSATION_KEY property is the otherwise obsolete precursor of the PR_CONVERSATION_INDEX, PidTagConversationIndex Canonical Property and PR_CONVERSATION_TOPIC, PidTagConversationTopic Canonical Property, which should be used instead.