Microsoft New Zealand and NetSafe say there's been a "significant increase" in reports of scammers trying to rip people off by claiming there's something wrong with their computer.
Netsafe's executive director Martin Cocker said the scammers try and legitimise their ruse by claiming to call from Microsoft.
The cold callers offer to fix compromised computers and ask for remote access to computers which can reveal credit card details or bank account numbers. Some people have allowed access and one is reported to have lost around $5000.
Mr Cocker says this pattern of scamming is not new and the scammers use the Microsoft brand as the company is known to have trusted experts.
"Unfortunately some people believe the calls are genuine and are led to believe they are doing the right thing by handing over private passwords or details. They can find themselves losing money or ending up with a computer infected with viruses or other malware that compromise their security," Mr Cocker says.
Microsoft NZ marketing and operations director Frazer Scott says the big message they want to get out to New Zealanders is that the company will never call them asking for remote access to their computer.
"We do not call customers at home saying that we have detected a problem with their computer. We will never ask for passwords or other private details in any forum," Mr Scott says.
Mr Cocker says their advice is to hang up immediately and report the incident to NetSafe.
"If you have given someone on the phone access and start to worry, then disconnect the machine from the internet and then hang up and report the incident to us. If you have given any bank details to a caller, then advise your bank as soon as possible."
Both companies are beginning a nationwide advertising campaign and writing to community groups to alert as many people as possible to be wary of these calls.
Classic scammer claims:
• Overseas caller states they are from Microsoft or a Microsoft certified technician.
• Suggests the victim's computer is infected and harming others online or that their ISP has identified their system as a problem.
• Will get the computer owner to give the caller remote access using a genuine networking service or website like logmein123 or teamviewer.
• They will use the 'Event Viewer' tool on the computer to highlight error messages which are supposedly signs of an infection.
• The cold caller will offer to clean up the infection and/or install security software and provide an ongoing support service costing anywhere up to $500.
How to deal with them?:
• Hang up the phone - engaging with or taunting these companies can lead to you receiving many more calls at all times of the day or night. Some technicians have resorted to threats or abuse to get computer owners to give remote access.
• If you do give access but become suspicious, disconnect the machine from the internet immediately. NetSafe has received some reports of these cold calling companies installing ransomware on the computer to ensure they get paid to unlock the PC.
• If you have previously given remote access, it may pay to check what has been installed on your computer and be certain there is no way for the company to continue accessing your system and files. Consult a trusted local PC technician if unsure.
• If you have paid money to these companies using a credit card, call your bank and discuss your options. If you sent funds via Western Union or another wire transfer service then the money is gone and cannot be recovered.
• To report the call or incident to NetSafe, either log the incident via its website https://www.theorb.org.nz/forms/scam-or-fraud/ or call on the NetSafe toll-free number 0508 NETSAFE (0508 638 723).