TechDish: How to Know You May Have a Virus Infection

Posted on: Fri, 07/16/2010 - 10:08 — us104_techdish

Good morning and happy TechDish Friday! We've talked many times now about antivirus protection: what tools to use, how to use them, and what to do and what not to do when your computer gets infected with a virus. But we've never really focused on how to know you may have a virus in the first place. And so without further adieu, that is what we'll be discussing with you here today on TechDish.

But first…Know Thy Computer

Be aware of your computer's normal behaviors. Do you normally get popups? At what sites? What does your antivirus software look like when it's running? What do alerts from your antivirus software look like when you receive them? What is the normal speed of operation of your computer?

If you aren't familiar with what is "normal" for your computer, you won't have anything to compare abnormal behavior against. Keep in mind that with every computer, speeds and performance can degrade over time as the computer "ages"; so we're not comparing performance of this year versus last year, or even this month versus last month. We're looking at rapid degradation of performance occuring in a span of minutes, hours, and days at most.

Common signs you may be infected with a virus

1. Your antivirus software tells you so

   This should be the most obvious sign, but is overlooked suprisingly often by users. If your antivirus software finds a virus, it will tell you. And it won't be an internet browser popup window, like those nasty rogue viruses that try to get you to purchase antivirus software.
   

2. The virus tells you so

   A virus that tells you and alerts you that it's there? Yep. Lately there have been virus attacks on normally "safe" websites that were themselves infiltrated by viruses. These viruses served up very professional and official-looking popups, telling you your computer is infected, and to click here to download or updated the antivirus software. If you do anything but close the window, you've clicked one too far. If you got to the point of entering your credit card information, cancel your credit card immediately. Seriously. And be careful closing that window, we've seen instances of even the red 'X' being mapped to downloading the virus rather than closing the window. Remember that little [Alt] + F4 trick, that's the keyboard shortcut to close a window.
   

3. You experience a degradation in performance

   Here's where knowing your computer's normal behavior can help you diagnose abnormal behavior. If your computer goes from running snappy smooth to slow and sluggish in a relatively short period of time, you might be infected.

4. You experience an abnormal amount of popups, from atypical websites

   Are popups getting the best of you when browsing websites where you normally don't see any? This is a common sign that you have a virus. The popups, while looking like they are being served from the websites you are browsing, are actually being served by the virus itself; either in an attempt to get you to download their software, or to make money off of ad revenues.

5. Your search results links take you to strange places

   This is called search page hijacking or redirecting. Basically, you search for something in Google (or Yahoo!, or Bing, etc.) and you get to the search results page. Then you click on a search result to get to the website that has the stuff you searched for. But wait! You didn't get to that website at all; you're now at a bland-looking site covered in ads of various sorts. You hit the back button and try a different link. Same thing. And again, and again, and again…same thing.

Rehash: Safe Browsing Habits

About a year ago we talked about Safe Browsing Habits. The information from that episode is still true today, with a couple things to add:

Lower risks by changing browsing habits

We see this in the shop quite often. A customer just got his computer back from a wipe/reinstall due to virus problems, only to be infected all over again by more viruses a week or two later. If this is you, it might be time to find some different websites to browse.

Not sure if a website is "safe"?

You're in luck, there's a tool for that! Or tools, rather. McAfee® SiteAdvisor® tests websites for spyware, spam and scams and applies ratings to them. Downloading the SiteAdvisor software allows you to see these ratings when you get to the site, and also on search results pages—so you'll know whether a site is trusted and safe before setting foot (er, mouse) in it.