You never open attachments in emails, you don’t click on suspicious-looking links, and you don’t download programs from random websites – so why is your computer getting viruses, adware, and a LOT of popups?
(And by the way, if you DO any of those things – STOP IT!)
You might not believe it, but a very large number of infections come from advertisements that have been hijacked on perfectly legitimate websites.
Internet advertising is a complex business, and a complex technical environment. By the time an ad shows up on a page you’re looking at, a dozen or more different systems on the Internet could have had a part in making that ad appear. Each of these component systems are big targets for hackers, who try to break into the process, so that some malicious bit of code gets into your system. That code can either get you to install something you think you need, or even install unwanted programs without you knowing about it. These programs can do any number of things, from generating popup ads on your screen to infecting your computer to act as a part of a network of computers that do bad stuff to other computers.
Here’s a recent article from ComputerWorld about how this works, if you want a little more detail.
So the question is, “How do I keep my computer from getting this junk?”
First and foremost, use good antivirus software. My favorite commercial antivirus software is ESET NOD32, but you can get reasonably good protection using the free versions of AVG or Avira. If you already have antivirus software, make sure it is being updated regularly.
If you’re on Windows, can I suggest that you DON’T use Internet Explorer? Because it is so tightly tied into Windows, it makes it easier for malware to get through the web browser and into your system. Google Chrome, Firefox, and Apple’s Safari are great alternatives – my favorite is Chrome.
One other thing that can help is to install an ad blocker into your web browser. These programs do just what you’d expect: They keep ads from showing up on web pages you visit, whether on Facebook, in your web-based email, or on your favorite motorcycle enthusiast or celebrity gossip sites. They’re not always 100% effective, but they really do help reduce the ads you see, and reduce your exposure to infected advertising.
The most popular ad blocker is AdBlock, and it’s free — though if you want to donate something to help its developers, that’s great. AdBlock works with Firefox, Chrome, and Safari, on both Windows and Mac OS X.
Another option for Chrome is µBlock, which works similarly, and uses a little less memory.
If you must use Internet Explorer, use AdBlock Plus – which, oddly enough, is unrelated to AdBlock, mentioned above. It’s the only reputable ad blocker for Internet Explorer.
This is a bit of a controversial topic. Most websites make money from the ads, and if you don’t view them, they don’t get as much money. So they don’t want you to block the ads. Until the online advertising environment deals with their security issues, though, most computer security experts still advise ad blocking software.
If you have any questions about ad blocking, or are having trouble with malware – no matter where it came from – feel free to contact me using the form here on my website.