ROCKLIN (CBS13) — A Rocklin pizzeria owner says someone tried to blackmail his business by taking control of his computers’ data.

It all started with Pete Lostritto opened an email he thought was an job application, but instead froze 90 percent of the shop’s files.

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“There wasn’t anything unusual looking in the email, it looked legitimate so we didn’t think it was anything out of the ordinary,” he said.

All of his bookkeeping and graphic files for his restaurant were hijacked and couldn’t be opened. The hackers asked for $400 ransom in the form of Bitcoin.

“They said we are holding the key to your computer for six more days and after six days its going to go up, so if you want your stuff pay now,” he said.

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The longer he waited, the more threatening the emails and the higher the ransom got. At one point, they wanted $2,000.

Jeff Dion, owner of PC Solutions in Auburn, says other local businesses have come into his shop with a similar problem, and there’s nothing he can do.

“They are the ones with the tool or the key or whatever means you need to do to get your data back,” he said.

Lostritto chose not to pay the money, and instead rebuilt his restaurant files from scratch. But he’s also learned the value of backing up.

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He says it cost him around $750 to rebuild his computer and to pay for an external hard drive where he now backs up his files. It took him several weeks to re-enter his data.