Once in a while I get a spate of various types of bounce messages (usually from System Adminstrator, indicating the addressee is unknown), which refer to a message I never sent. The message is always some kind of spam advertising.
I notified my ISP but they sent me a canned answer saying to check for viruses. No virus on my system, according to Norton, and none of the bounce messages are from email addresses in my address book or that I recognize.
I suspect that someone is spoofing my email address to send spam. Unfortunately the bounce messages do not include the full header for the message they received.
Any other possibilities I’m overlooking here?