I am constantly getting emails saying "mail delivery system" delivery status notification (failure)

Hello,

Are these eMails you sent yourself?

Also, that nessage could be spammers trying to get spam or malware to you in a backwards way...

http://blog.onlymyemail.com/delivery-status-notification-failure-virus/

Open email source, obscure your email address and name etc (may be in more than one place) and post it all here.