(CNN) —  

Ransomware is a growing Internet scam that preys on fear. The online shakedown uses sophisticated methods to hold data hostage unless the user pays a fee of up to several hundred dollars.

Bruce Snell of McAfee Security offers consumer tips on how to avoid ransomware:

– Think before you click. If something looks suspicious or too good to be true, it is probably best avoided.

– Don’t click on unexpected links or attachments in e-mails. If a friend sends an e-mail with an attachment out of the blue, contact that person directly to make sure he actually sent it. A quick phone call or text message asking “Did you send me a file?” will do wonders for keeping you safe.

– Use an external hard drive or online backup for your important files.

– Use browser plug-ins to make browsing safer. McAfee offers a free plug-in called Siteadvisor (http://www.siteadvisor.com) to warn of dangerous links. Another great tool to avoid potentially dangerous popups is Adblock (http://adblockplus.org). Its primary function is to avoid ads on websites, but it also helps prevent sneaky pop-up ads that trick people into downloading malware.

– Run some sort of anti-malware product on your computer. Most ransomware can be prevented with up-to-date security software. And keep your system updated. A lot of malware takes advantage of security holes (vulnerabilities) in either the operating system or installed applications.

– The federal government offers a resource at http://www.onguardonline.gov/ offering guidance and contact information on dealing with cybercrime.