New scam holds your computer files for ransom

If you're not backing up your computer files on a daily basis, now may be the time. The National Consumer's League is warning about a pernicious and growing malware scam that infects users computers with something called "cryptolocker."

Spread via email, bogus websites and Facebook videos, the malware encrypts the contents of your hard-drive, making it impossible for you to retrieve your files. The moment the virus infects your computer, it tells you with a ransom note that demands hundreds of dollars in untraceable payments to "decrypt" your system. But according to the FBI, decryption is not possible.

Once files have been corrupted, the only computer that can get into them is owned by the attacker. The FBI says the only way to fix your system is to wipe it clean and restore your data with a backup copy of your files.

Naturally, the best way to deal with this nightmare is to avoid it. Make sure your security software is up to date, and don't open email files that appear suspicious. What makes files suspicious? They're sent by an unfamiliar user or appear to be coming from a friend, but with a message that seems unlikely, like "OMG. Look at this" or "This video is amazing."

If you're tempted to click on the video, reply to the sender first, asking if this came from them or if their email address has been hijacked. Waiting a few extra minutes for a response could save you a bundle in time and money.

Chris Duque, a retired Honolulu police detective who has become an expert in cybercrime, says he thinks the virus is most likely to be caught by Facebook users, many of whom click on shared videos. The tip-off is likely to be a message that says you'll need to download some software to watch. Don't do it. The moment you authorize the software download, it opens your system to the malware. The next warning is the pop-up ransom demand. And then it's too late.

Cryptolocker software is no joke, Duque says. It can render your computer completely unusable, so think twice before becoming so curious about that video that you're willing to accept a suspicious download. Worse, though Facebook appears to be a likely way to spread the virus, law enforcement officials are unsure about where the virus starts and how it spreads. If you often search the web and are likely to download files, be sure to back up your system.