Recipient.Sendable Property (Outlook)
Returns or sets a Boolean value that indicates whether a meeting request can be sent to the Recipient. Read/write
This property corresponds to the MAPI property PidTagRecipientFlags. It returns True if PidTagRecipientFlags is equal to 0x00000001. Setting the property changes PidTagRecipientFlags accordingly.
This property applies only to a recipient of a meeting request. If the recipient is not on a meeting request, getting and setting this property does not do anything.