Scammers posing as technology support experts are stealing thousands of dollars from West Australians.
Victims from Perth and the South West have lost up to $10,000 each in a recent spate of scams.
In many cases, the fraudsters claimed to work for big information technology companies such as Microsoft or Telstra.
An elderly Brighton man named Peter received a call from a "Telstra employee" who offered to upgrade his computer's Windows XP operating system for $5.
Peter gave the caller access to his computer, logged into his internet banking and used his credit card to pay the "fee".
He is still trying to recover the $10,000 the scammer stole.
Busselton pensioner Merv, 78, was persuaded to give his bank details to an Indian man who said his home computer had viruses.
"The bloke said he could get rid of the viruses for good for $400 and I thought, 'well, $400 sounds pretty good'," he said.
"He opened up a PayPal account in my name but said the first $400 had been rejected so I shot straight down to the bank."
When Merv said the caller's name was "Jack Dawson", the bank attendant knew he had been scammed.
Jack Dawson was the name of Leonardo DiCaprio's character in Titanic.
"I should have woken up to it because I update my anti-virus at least once a week, but I'm still learning this stuff," Merv said.
"I think I was targeted.
"The wife's not letting me forget it either.
"Just be careful about giving anyone your bank details or your card number because then they can get into everything."
A sharp rise in the long- running scam prompted a warning from Consumer Protection Commissioner Anne Driscoll.
She said the scam recently took a turn for the worse, leaving victims with compromised computers and hefty losses.
"Hang up on anyone who calls out of the blue claiming to be from Microsoft, Windows support, Telstra, BigPond, Apple or any reputable company wanting access to your computer to fix a problem," she said. "These companies never do this unless you contact them first.
"Never allow anyone to have remote access to your computer, unless you initiated the contact.
"Your personal information is the key to unlock your financial accounts, so guard them carefully." Visit www.scamnet.wa.gov.au or call 1300 30 40 54.