I need to set Accept / Decline EmailMessage object in Microsoft exchange service code

Question

I need to set Accept /Decline of EmailMessage object in Microsoft exchange service code. Where message sender wants a response to a message from receiver.

    EmailMessage emailMessage = new EmailMessage(service);
    EmailMessage.Subject = "test";
    EmailMessage.ToRecipients.Add("[email protected]");
    EmailMessage.Body = new MessageBody("test");           
    ExtendedPropertyDefinition PidTagResponseRequested = new ExtendedPropertyDefinition(0x0063000B, MapiPropertyType.Boolean);
    EmailMessage.SetExtendedProperty(PidTagResponseRequested, 1);
    EmailMessage.SendAndSaveCopy();