I keep getting a "postal failure" from a bobs lighting that I neither sent or have any connection to. It seems come after I revive other mail or send mail. Should I be concerned? I have tried to contact them (in aus) to no success. Tom
This could be the result of what used to be called a "joe job", a spammer using your email address as their From: so you get the bounces instead of them. There isn't much that can be done if this is the problem.
It could also be a signal that your email account has been compromised and it being used to spam. Changing your password and running a spyware scan on your computer could help fix the problem if this is the issue.