This post is further to one earlier today - "Email query/problem" - I wasn't sure how to amend my earlier post.
I've just found my email has another lot of auto replies and undelivered notices about messages that I have not sent. As far as I can figure out, a message purporting to be from me has been sent to all the addresses in my contacts list. This list (added to by AOL with every new addressee) includes my own Hotmail address, and when I checked that I found that the message was in fact a link to a healthcare website. It seems like a scam to direct people there. I'm not sure what to do to stop this - would deleting all contacts work? - or uninstalling all AOL stuff and getting a new email account? (AOL is no longer my ISP).
Advice needed.