The opening of the letters (namely the opening):
1) the Field "Disposition-Notification-To" in the headers is precarious, guarantee that you will receive notification no
2) the Picture in the message src is controlled by the server a unique address-type src="firstname.lastname@example.org
" - as unreliable, the reader is likely to immediately pictures will not show
Links through a redirect site.ru/go?url=http://www.ru
or some such public service.