IMessageSummaryEnvelope Property

Envelope Envelope { get; }

Property Value

The envelope of a message contains information such as the date the message was sent, the subject of the message, the sender of the message, who the message was sent to, which message(s) the message may be in reply to, and the message id.

This property will only be set if the Envelope flag is passed to one of the Fetch or FetchAsync methods.

Reference