Mail delivery failure messages for email I've never sent.

Most likely, it's people sending spam, and spoofing the 'From:' header so that it looks like it's coming from your email address. If they send the spam to an address that doesn't exist, it bounces back to whoever it came 'From:', which in this case looks like you.

I get the same thing (tons of them) and it seems to me that either the spammers use the "Mail Delivery error" to sneak through the spam filter or that they just use some random return address that happens to be yours, but I sure would like to hear an expert analysis of these and whether it's possible to stop them. A large portion of my spam currently looks like this: From: [email protected] - Subject: Returned mail: User unknown From: [email protected] - Subject: Delivery Status Notification (Failure)

There are various viruses that function by infecting someone's computer, going into the person's address book, and sending out copies to various people in the address book. The sneaky bit is that they use other names from the address book for the Sender field to make the mail look more "natural" or something. Hence innocent parties like yourself getting dragged into the melee of bounces and returned mail. So that's another possibility.

You're screwed. Google for "joe job", and you'll see why. I must have pissed off a spammer at one point, because I get about 600 of these bounces every day, with various repugnant subjects, and a good number of them still get through my multiple levels of filters. I'm ready for some violence.

There are various viruses that function by infecting someone's computer, going into the person's address book, and sending out copies to various people in the address book. http://www.informit.com/articles/article.asp?p=24374&seqNum=4

FWIW, the bayes filter in thunderbird quickly learned to spot these.

something to be aware of - someone might send you a nasty email because they think you're the source of the spam. happens less these days, because people are used to span, but if it happens don't think someone suddenly hates you, it's just mistaken identity...

Spammers send so many emails faked from my work's domain that AOL has now blocked us. And there seems to be little we can do about it. Grr!

bonaldi: Have you looked at http://postmaster.aol.com/? No ISP should block email simply on the basis that it comes from a 'known' spam email address. The 'From:' header is just far too easy to forge, with the result that innocent bystanders get their emails blocked, as we have seen here. What does make sense is for ISPs to block servers that are acting as open relays that spammers are sending email through. This is a misconfiguration and bad security on the part of the company that is running the open relay. If this is what's happening with you, bonaldi, then the IT bods where you work really should check out their email servers and make sure they're not relaying a load of spam.