By Andrew Kramer

PHILADELPHIA (CBS)–After one of the largest cyber attacks ever over the weekend, an expert from Philadelphia suggests steps you can take to make sure ransomware doesn’t wipe your computer totally clean.

Precaution is one of the best ways to avoid cyber attacks says Drexel University professor Rob D’Ovidio, who studies high tech crime:

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“Be leery of unsolicited emails, emails coming from people you don’t know that are asking you to open files, that are asking you to click on suspicious links.”

World’s Biggest Cyberattack Hits 150 Countries And The Threat Is ‘Escalating’

Otherwise you, too, could become a ransomware victim.

“User gets duped into clicking on a link that takes them to a page that contains malicious software that’s downloaded onto your machine,” says D’Ovidio.

Which then prevents you from using your computer.

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“In this case they’re asking people for $300 to unlock your machine,” he says.

That ransom eventually doubles, but D’Ovidio says you should never pay it under any circumstance. Instead…

“You certainly want to make sure you have access to a very recent backup,” he says. “Wipe the machine, reinstall the operating system and restore all your files. You might lose a little work, that’s unfortunately the price to pay.”

Regardless, D’Ovidio says this whole situation could worsen as the work week begins.

“It hit over the weekend. In certain countries the business week was done already, so when they go in and turn on their computers Monday morning, you’re going to have a further spreading.”

In other words, he says, IT departments around the globe will likely be extra busy in the morning.

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