2.2.7.21 PidLidDelegateMail
DAV property name: http://schemas.microsoft.com/mapi/delegate_mail
Data type: PtypBoolean ([MS-OXCDATA] section 2.11.1.6)
The PidLidDelegateMail property ([MS-OXPROPS] section 2.92) gets or sets a value that indicates whether a delegate responded to the meeting request. True if the delegate responded to the request; otherwise, false.