Auto-reply
auto-submitted\:.{0,60}auto-replied
automated.response
autoreply
content-type\:.{0,60}message\/delivery-status
content-type\:.{0,60}multipart\/report
mailer-daemon
report-type.{0,60}\=.{0,60}delivery-status
report-type.{0,60}\=.{0,60}disposition-notification
subject\:.{0,60}delivered:
subject\:.{0,60}undeliverable\:
subject\:.{0,60}out.of.office
X-FC-AutoForward-By
X-FC-Forwarded-From
X-FC-Machinegenerated
Content-Type\: message\/disposition-notification  # for Exchange/MS OutLook users
Disposition\: manual-action\/MDN-sent-automatically\; displayed # Disposition: manual-action/MDN-sent-automatically; displayed