ReallyCurious asks: "Recently, I've noticed a lot of junk email in my inbox reporting 'Mail delivery failure' or 'Undeliverable'. Some of these had documents attached, so I figured this was just a worm variant. But these messages keep coming. I worry that my machine has been turned into a 'Spam Zombie'. I don't see any suspicious processes running, but maybe it only runs for a few seconds, and at irregular times. I run a Windows 98 laptop, sometimes wirelessly connected to broadband (a few hours a day, on average), but I had to remove my virus software years ago because it was locking my system up, so I'm wide open. I've tried to be a good citizen and have been shopping for new virus software, but prices are running $40-$70, and most of these are just for upgrades (not even counting the mandatory 'subscriptions')! Is there an open or free virus fighting solution that's reliable and available for Windows? I'd be happy to run it ASAP."