OK - so now I'm sending blank questions??
What I tried to say above was:
A couple of weeks ago a friend told me that she had been getting mail returned to her that she had never sent and she didn't even know the address that had rejected them. There were attachments. Since I've got good virus protection, I told her to send one to me so I could look at the headers - just in case I could figure out the problem.
She sent one to me & as expected the attachment had a virus, so it was promptly deleted and I did a virus scan. Everything came up fine according to McAfee online.
A couple of days ago, I received something from "Mail Delivery System" saying that something I had sent could not be delivered due to the attachment. Same thing - I hadn't sent it & I don't know the address. This time there was no attachment because it had been translated into a bunch of gooblygook. I deleted it & did a virus scan - everything was ok. Today I just got another one. I'm in the midst of another virus scan right now.
What else can or should I do?