KnownStringMetadataFieldsWebReferenceAttachmentPath Field

Outlook email object has an attachment(s) that are by web API reference only (see also KnownBooleanMetadataFields.HasWebReferenceAttachment), i.e., the attachment data must be retrieved by web API and is not directly part of message object.

[KnownMetadataAttribute(IsEmailType = true)]
public const string WebReferenceAttachmentPath = "WebReferenceAttachmentPath"