A woman accused of being involved in a huge scam that duped a million US consumers using ‘scareware’ antivirus programs has been fined $163 million (£101 million) by a federal court.

In a long-running case first brought by the FTC in 2008, Kristy Ross was accused of conspiring with other defendants involved with two companies, Ukraine-founded Innovative Marketing (IMI) and ByteHosting Internet Services, to distribute rogue antivirus software that sold licenses to ‘fix’ non-existent malware infections.

Bogus programs included some of the most active on the scareware market, including WinFixer, WinAntivirus, DriveCleaner, ErrorSafe, and XP Antivirus to name only some identified by prosecutors.

Victims would be asked to pay between $40 and $100 to remove the claimed malware; a staggering 320,000 US consumers – and possibly a million - are believed to have been scammed by the company’s software over a period of years, making it the largest software fraud of its kind ever exposed.

After carrying out the scam since at least 2004, four years later three thousand consumers had filed complaints, which brought the matter to the FTC’s attention.

Ross said she knew nothing of the fraud and was merely an employee of the company, Innovative Marketing. The court utterly rejected that claim, deciding that she had acted as IMI’s sales and marketing director between 2002 and 2008, making numerous executive decisions.

Prosecutors uncovered evidence that Ross even dictated the English language wording of some scareware campaigns, specifying the level of sales aggression that should be used.

Action against others involved in the case has already resulted in a judgement that returned an average of $20 to large numbers of victims stung by the operation.

What the case has brought to light is the huge multi-national complexity of scareware frauds and the effortless profits they generated. IMI turned out to be a company with 600 employees in the US, Ukraine, Argentina and India creating, distributing and marketing rogue programs, often using legitimate websites.

The court found that Ross was only one cog in that money-making machine, albeit an important one.

Although far from dead, scareware is no longer the crime of the day; many criminals have now moved on to even more aggressive 'ransom' attacks in which users are forced to pay up by locking or disrupting their PCs.