Microsoft has called in British police to stop an e-mail scam that urges users to call a special number to get help securing Windows.
The number, which connected the caller to a real Microsoft number but charged more, was disconnected yesterday (6 February).
A Microsoft spokesman confirmed the company was "working with UK police to investigate the e-mail scam".
"We don't think it is appropriate that somebody should defraud our customers and, of course, it is our obligation to pursue any such action," the spokesman said.
E-mail messages claiming to be from "Microsoft Technical Support" and told readers to call a national rate number in the UK to obtain a "vitally important" Windows security update first appeared late December.
Charges for calling a national rate number vary by phone operator, but are typically between 8p and 10p a minute. The owner of the number would typically only get a small part of that, a spokeswoman for UK telecoms regulator, Oftel said.
The scam is small, generating only several hundred pounds for the perpetrators. Microsoft has asked the telephone carrier involved that proceeds will be frozen pending police investigation.
Even though the 0871-750-1250 phone number in the e-mail can only be reached from inside the UK, the e-mail has been sent to users around the world and has caused some confusion.
Microsoft advises users to always use a trusted reference when contacting the company such as numbers listed in manuals or the official Microsoft website.