I keep receiving emails that appear to be sent by ME, advertising truly revolting stuff. What could be causing this? Thanks.

If you take a good look at the header in the mail (Maybe you'll have to switch the extended header mode on somewhere). Take a look and probably you will find that someone has logged on to a mailserver and typed your e-mail address as the sender, you can actually send mail by giving the mail server it's needed parameters. All you need is some knowledge about how mail works. Don't worry I'd say... As long as you don't suffer from split personality :).

In my opinion you are almost certainly infected with some type of worm or virus. I would download AVG, or AT LEAST run an online scan right away. Copy and paste the following links- For Free Antivirus protection use this link: http://www.grisoft.com For an online scan use this one: http://housecall.antivirus.com Jimi_l

There are no viruses involved. This is just another example of mail address spoofing from one of the many spammers. Generally the email address is a fake one but is made to appear as being real by using Hotmail.com or Yahoo.com Some are now using YOU as the sender (only your name), and if you look at the headers, as suggested, you will see the it came from some foreign-looking origin. Not much you can do about it. You could contact you ISP for advice.

How can you say that without question? Many Viruses use your address book and E-mail client to replicate themselves or at least wreak havok and most everyone's own E-mail address is in there address book.I have heard of address spoofing for sure but certainly not to the degeee that I have seen viruses being repopulated. These are the facts that I base my opinion on. Jimi_l

In my opinion you are almost certainly not infected with some type of worm or virus. This is a common spoofing technique. I have multiple email addresses, and the volume of spam I receive is quite large. Of the emails I have received where my address has been the From address, all so far have been due to spoofing. That's not to say it could not have been a virus, just that in my experience it is one of the least likely scenarios. As AndreasF suggested, take a look at the full headers. I can't tell you exactly how to do this because you did not mention what mail program you are using. But there should be a way to do this.