Is Your PC Infected?

Is Your PC Infected?Not every system oddity is due to a virus, worm, or bot. Is your system slowing down? Is your hard drive filling up rapidly? Are programs crashing without warning? These symptoms are more likely caused by Windows, or badly written legitimate programs, rather than malware. Today's viruses, worms, and so-called bots - which turn your PC into a zombie that does the hacker's bidding (such as mass-mailing spam) - are not going to announce their presence. Real viruses operate in the background, quietly altering data, stealing private operations, or using your PC for their own illegal ends. This makes them hard to spot if you are not well protected. However, here's what to do if you suspect the worst.

There are signs that indicate that your PC is actually infected. A lot of network activity coming from your system (when you're not actually using Internet) can be a good indicator that something is amiss. To put a network status light in your system tray, follow these steps: In Windows XP, choose Start, Control Panel, Network Connections, right-click the network connection you want to monitor, choose Properties, check "Show icon in notification area when connected," and click OK.

If you are interested in being a PC detective, you can sniff around further for malware. By hitting Ctrl-Alt-Delete in Windows, you will bring up the Task Manager, which will show you the various processes your system is running. Most, if not all, are legit, but if you see a file name that looks suspicious, type it into a search engine and find out what it is. Want another place to look? In Windows XP, click Start, Run, type "services.msc" in the box, and press Enter. You'll see detailed descriptions of the services Windows is running. Something look weird? Check with your search engine.

Once you are sure your system is infected, don't panic. There are steps you can take to assess the damage, depending on your current level of protection:

- If you do not have any antivirus software on your system (shame on you), or if the software has stopped working, stay online and go for a free scan at one of several Web sites. There's McAfee FreeScan, Symantec Security Check, and Trend Micro's HouseCall. If one doesn't find anything, try two. In fact, running a free online virus scan is a good way to double-check the work of your own local antivirus program. When you're done, buy or download a real antivirus program.

- If you have antivirus software, but it is not active, get offline, unplug wires - whatever it takes to stop your computer from communicating via the Internet. Then, promptly perform a scan with the installed software.

- If nothing seems to be working, do more research on the Web. There are several online virus libraries, where you can find out about known viruses. These sites often provide instructions for removing viruses - if manual removal is possible - or a free removal tool if it is not. Check out GriSOFT's Virus Encyclopedia, Eset's Virus Descriptions, McAffee's Virus Glossary, Symantec's Virus Encyclopedia, or Trend Micro's Virus Encyclopedia.

Assuming your system is now clean, you need to make sure it stays that way. Preventing a breach of your computer's security is far more effective than cleaning up the mess afterwards. Heard this one before? You must run antivirus software and keep it up to date or else your PC will be infected. Also, make sure you keep all security software up to date. Security tool without regular, easy (if not automatic) updates is not worth your money or your time. Speaking of updating, the same goes for Windows. Use Windows Update (it's right there on your Start Menu) to make sure you are getting all of the high priority updates.