Best Buy's team of security experts has been fighting several schemes invoking the Richfield-based retailer — including one to people who had purchased Geek Squad support plans.

Delray Beach, Fla., resident Diane Belz, 68, lost $1,800 because of the scheme. A woman who lives in Boynton Beach, Fla., lost $52,724.

Belz received an e-mail on March 1 claiming to be from the Geek Squad. She had opted for a Geek Squad technical-support plan when she bought her MacBook in 2017. The e-mail stated that her support plan had been extended for three years and her credit card charged $392.95. If she wanted to reverse the charge, she would need to call the customer support number in the e-mail within 24 hours.

She dialed the number and ended up giving them information that allowed the perpetrators to steal her money.

"What these scammers are doing to these customers is absolutely terrible. Best Buy has a team of professionals constantly working to find more ways to stop these scammers from succeeding," a Best Buy statement said.

Best Buy does not generally call customers unsolicited, the statement said. If there are any questions, customers should err on the side of caution and call 1-888-237-8289 (BEST BUY), or use a contact method on BestBuy.com.

Known across the internet as the "Geek Squad scam," the scheme also comes disguised as other technical support plans, including Norton Anti Virus and other trusted brands. Scammers send out e-mails "phishing" for likely subscribers.

"Very few scams like this get reported," said Ora Tanner, a researcher on the Aspen Tech Policy Hub's recent project, Protecting Older Users Online. "And that's because the senior is ashamed. They think, 'How could I have allowed this to happen to me?' They tend to hide it. That allows it to perpetuate."

Business impostor fraud topped the Federal Trade Commission Consumer Sentinel Network's tally of types of fraud against consumers ages 60 to 69 and 70 to 79 for the first time in the fourth quarter of 2020, knocking government impostors from the top spot.

Reports of business impostor fraud by consumers in those age groups increased from 14,914 in 2016 to 44,114 in 2020. Consumers in those age groups reported losing $46.36 million to business impostor fraud last year, with the average victim losing $898.

Targeting seniors has existed for as long as seniors have been going online. Years ago, the Nigerian prince scam convinced victims that the senders were heirs to a ruler who needed someone in the United States to hold onto their fortunes — if victims sent money to prove they could be trusted.

Dating scams targeted lonely widows and widowers with promises of companionship but left them with lower bank balances. Then came the pop-up technical-support scams that locked up victims' computers until they subscribed to virus cleaning or malware removal software they didn't need.

The newest scams are descendants of those, but rely on victims' familiarity with legitimate services.

The goal is the same: to gain control of victims' computers and ultimately their money. And once money is transferred, there's little any bank or law enforcement agency in the U.S. can do to help get it back.

When Belz received the e-mail stating that $392.95 was charged to her credit card, she followed her first instinct. "I called and said I can't afford to renew for that much. I want to cancel."

Next Belz — who filed a complaint with the Florida Attorney General's Office — received an e-mail from the scammers saying they mistakenly refunded $4,900 to her credit card and she needed to call to arrange to return the overpayment. "I called them right back to find out how to reimburse them."

She was told to download a program called Team Viewer and type in credentials that gave the scammers control of her computer. They quickly opened her web browser and found her bank account link saved among her favorites. When they accessed that website, her login credentials were already filled in.

Belz also was told she needed to send more money to return the overpayment and get her $392.95 back. She was told to go to Best Buy and purchase gift cards for $200 and $500, then go to Walmart and buy another $200 gift card. At the scammers' direction, she scratched off the film that hid the cards' PIN numbers and read the numbers over the phone — enabling the perpetrators to instantly transfer the value of the gift cards to themselves.

Best Buy's fraud prevention team is constantly working to prevent the scams, working with law enforcement and other retailers, a company spokesperson said.

Best Buy offered tips, including stopping yourself before you click on a link or share personal information and thinking through whether it could be a scam. Often, if someone is pressuring to act quickly, it is a scam.

If you receive a call or e-mail asking for payment by gift card, know that it's a scam, the retailer said.

Best Buy has modified some of its gift-card policies in response to scam reports.

Employees are trained to look for signs that gift-card customers may be victims of a scam, the company said. Per-person limits on purchases have been reduced from $2,000 per gift card and $6,000 per day to $500 per card and $2,000 a day. Checkout terminals display warnings about gift-card scams that customers must read before their purchase is finalized.

Staff writer Catherine Roberts and the South Florida Sun Sentinel contributed to this report.