Keep in mind that there are some virus and/or trojan programs out there that don't even have to be opened on the PC in order to do their damage. Simply viewing the message in a preview pane is enough to activate them.
Again, I place the blame for these virus and trojan problems in the majority of the world squarely on BOTH the writers of said programs and Microsoft. If M$ didn't have so much bloat crammed into their software, which leads to all sorts of holes not to mention it being slower then heck, huge amounts of the things that virus and trojan programs try to do wouldn't even be possible.
That's one of the main reasons why I like running my Amigas. "Security through obscurity!"
