How to boost your malware defense and protect your PC

To help secure your computer against malware:

• Build up your computer's defenses
• Do not be tricked into downloading malware

Build up your malware defenses

Install antivirus and antispyware programs from a trusted source

• Never download anything in response to a warning from a program you didn't install or don't recognize that claims to protect your PC or offers to remove viruses. It is highly likely to do the opposite.
• Get reputable anti-malware programs from a vendor you trust.
  • Microsoft Security Essentials offers free real-time protection against malicious software for your PC.
  • Or, choose from a list of Microsoft partners who provide anti-malware software.

Update software regularly

Cybercriminals are endlessly inventive in their efforts to exploit vulnerabilities in software, and many software companies work tirelessly to combat these threats. That is why you should:

• Regularly install updates for all your software—antivirus and antispyware programs, browsers (like Windows Internet Explorer), operating systems (like Windows), and word processing and other programs.
• Subscribe to automatic software updates whenever they are offered—for example, you can automatically update all Microsoft software.
• Uninstall software that you don't use. You can remove it using Windows Control Panel.

Use strong passwords and keep them secret

• Strong passwords are at least 14 characters long and include a combination of letters, numbers, and symbols. Find out how to create them.
• Don't share passwords with anyone.
• Don’t use the same password on all sites. If it is stolen, all the information it protects is at risk.
• Create different strong passwords for the router and the wireless key of your wireless connection at home. Find out how from the company that provides your router.

Never turn off your firewall

A firewall puts a protective barrier between your computer and the Internet. Turning it off for even a minute increases the risk that your PC will be infected with malware.

Use flash drives cautiously

Minimize the chance that you'll infect your computer with malware:

• Don't put an unknown flash (or thumb) drive into your PC.
• Hold down the SHIFT key when you insert the drive into your computer. If you forget to do this, click  in the upper-right corner to close any flash drive-related pop-up windows.
• Don't open files on your drive that you're not expecting.

Don't be tricked into downloading malware

Instead, follow this advice:

• Be very cautious about opening attachments or clicking links in email or IM, or in posts on social networks (like Facebook)—even if you know the sender. Call to ask if a friend sent it; if not, delete it or close the IM window.
• Avoid clicking Agree, OK, or I accept in banner ads, in unexpected pop-up windows or warnings, on websites that may not seem legitimate, or in offers to remove spyware or viruses.
  • Instead, press CTRL + F4 on your keyboard.
  • If that doesn’t close the window, press ALT + F4 on your keyboard to close the browser. If asked, close all tabs and don’t save any tabs for the next time you start the browser.
• Only download software from websites you trust. Be cautious of "free" offers of music, games, videos, and the like. They are notorious for including malware in the download.

From  http://www.microsoft.com