Re: What ?
1. Back when I still ran Windows, we got a virus infection from a dodgy ad on a legitimate, non-adult website. So dodgy or adult websites aren't always the problem.
2. Executable attachments really ought to be filtered out at the server level, or at least require several additional steps to download and run them, including a "yes, I'm quite aware that this could infect the computer, but I was expecting this file and I know what it is" confirmation.
3. ALWAYS turn OFF "Hide extensions for known file types" in Windows. What a misfeature! I once spotted a virus on our (Fortune 500) business network, as I had this turned off and could see that the "folder" was actually an executable, and the real folder was hidden.
4. Not sure what viewing emails as plain text is supposed to solve. But the email software had BETTER NOT run any scripts in the email.