e mails being sent without instruction

[parkinson40]

Hi
we suddenly started to get e mails about stock/shares that we could buy(if we had lost our marbles.).We ignored these and deleted them
Suddenly our computer has started sending the emails on to other addressess some seem to go through some seem to go to non known addresses or returned to sender.
I cannot see how to stop this
any ideas

[Raptor]

Scan for viruses/spyware.

[Fed]

Especially scan for trojans, although there has been some discussion about Ewido lately I'd still use it first.
http://www.ewido.net/en/download/

[GX1_Man]

Have a read here also:

http://www.google.com/search?hl=en&q=zombie+mail

[parkinson40]

well I  downloaded defender then avg then trojan remover these all removed some spyware/trojan etc.
however the e mails went again.The machine shows them as failed as the receipiant doesnt exist(some must get though.
the only thing I can think to do is buy the stock and perhaps they will go away
We have also now started to get emails trying to sell me *censored*.(up to 10 a day) perhaps they know something I do not.
We are running windows xp with f secure protection.
any ideas ( as my wife is now very suspicious!)

[patio]

I would contact your ISP about changing the e-mail account...unfortunately once those leeches get your addy who knows how many times it has been passed on...
Are you using any filtering software on that e-mail account ? ?

patio.  8-)

[Fed]

Did you try Ewido?
Hint, you will need to update it prior to scanning.