Very strange, Clive. I don't understand how a virus could be activated from an email when only viewed on the server, as, at that point, nothing has been downloaded to your machine. I have been using F-Secure since 2005, and nothing has ever got past it. In fact, the one and only time I have had an infection, was when I was still using Norton! I can only guess you were very unlucky, and the virus slipped through before F-Secure's scheduled update downloaded the definitions to protect you from it. At least you seem to have got rid of it, thankfully.