Occasionally I will get a returned message in my junk mail folder saying something like xyz@123.com was not a valid email address etc. and then the body of the email is a spam message (which I have obviously not sent out). The name of the sender is also not my name, but the email address is. How and why do they do this and how can I stop it?
Someone is spoofing your email address in the “From:” field - this is pretty simple to do, and there isn’t really anything you can do to stop it. Won’t do anything to hurt you though.
Biddee, you can read more about this phenomenon here. Be sure to read the Eweek mag article by Jim Rapoza.
Not much you can do to stop it unless virus-writing becomes unpopular.