LAS VEGAS -- The newest threat to your computer may be one of the nastiest and most vile viruses ever seen. It can literally destroy every file on your computer and it's nearly impossible to get rid of it.
This new threat is called ransomware because the virus literally kidnaps your files and holds them for ransom unless you pay the sender cash. The virus can't be detected by most virus protection software on the market.
Computer viruses have been around for decades, but the latest incarnation is particularly nasty. It's called ransomware.
"It would not go away. I could not close it and go on," said UNLV professor Kathy Espin.
She learned the sobering lesson about ransomware the hard way.
"On this screen, there was a countdown and I had 72 hours to come up with the money," she said.
In her case, the amount was $300. She refused to pay and went to two computer repair companies who -- in the end -- took more than $300 from her, but didn't fix the problem.
"Not all, but 90 percent of the files on my computer had been corrupted," Espin said.
She lost pictures and documents and it seemed no one could tell her how this happened. Espin asked 8 On Your Side for answers and got them.
Paul Anderson of Anderson PC, the foremost ransomeware expert in the valley, gave this explanation.
"It is a program that gets installed on your computer. It encrypts files. It essentially packages them up into a safe and tucks them away where you can't get to them and then holds you ransom," Anderson said.
He says nine times out of 10, it is the user who unknowingly installs it.
"The reality is this is a virus that people install themselves. It comes usually as an email attachment often in a zip file. People will open that up and look at a file inside that and install it themselves. It is a self-inflicted wound and very rarely comes in any other fashion," he said.
The virus is usually attached to an email from that appears to be from someone you know. It is often in a Zip or PDF file. If you open it, your virus protection software ignores it.
Espin admitted, she was opening email documents moments before ransomware struck her computer.
Many websites suggest paying the ransom to get en encryption code to free your files. Users say it works about 50 percent of the time. Anderson says paying the criminals isn't the best option, but there is nothing you can do to get your files back once the computer has been hit. He says the only real protection is to have all your files backed up.
"The preventative medicine of having a backup and having someone help you restore the backup is the best case scenario."
Also, if the virus strikes while you are connected to a USB or hard drive, those files are also likely corrupted and lost forever. So, it's best to do your backup using the cloud or services like Carbonite.com.