Imagine hackers holding your computer files hostage—and then demanding money to get them back. It's called ransomware, and if you are a victim of it, you’ll get a message on your screen that says your files are being held until you pay up. Don’t click on that message window unless you are willing to pay.

To make sure it’s not just a phony pop-up, Consumer Reports says to close your browser and if it comes back, then you may have a problem. If you have a good backup of your data, you won’t need to pay the ransom. But if you don’t, you might actually need to pay the hackers to get your files back. If you do have a backup, you can transfer your files to a clean computer. Or, you may be able to rebuild your system. A computer professional can help with this if you don't have the skills yourself.

To make it harder for hackers to gain access to your computer, experts at CR say, keep your operating system and all software, including security software, up to date. Even better, turn on automatic updates so you don’t have to think about it. Consumer Reports urges using preventative measures and says read any pop-up very carefully before clicking, even on a trusted website.

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