Microsoft has named and shamed four more computer dealers it caught hawking illegal software.

The software giant has reached settlements with Clarion Computers in Swansea, Surf-IT Computers Limited in Farnborough, Little Laptop Shop in Huddersfield and Custom PC Shop in Telford.

All four admitted to selling customers illegal software in the past six months and have agreed to "work more closely with Microsoft to ensure they understand the software company’s licensing policies”.

Microsoft timed the announcement to coincide with the launch of Consumer Action Day, a global initiative designed to expose the dangers of counterfeit software and clobber traders who sell it.

The vendor claims the number of incidents being reported rose from 67 to 423 year on year in September, following the launch in August of new Microsoft technology enabling consumers to detect they have been duped.

In the past two years, Microsoft has received more than 150,000 reports worldwide from people who unknowingly purchased counterfeit software.

Michala Wardell, anti-piracy manager at Microsoft UK, said the vendor is committed to helping legitimate PC dealers by stamping out unfair competition.

“Without the tips and reports we gratefully receive from consumers, these traders would still be carrying out their illegal practices today,” she said.

Wardell also issued a warning about the growing threat posed by online operators.

“As more people shop online to find the best bargains, the number of counterfeiters posing as online legitimate businesses has gone up,” she explained. “Unlike retail stores, counterfeiters can create a professional-looking web site in minutes. People should be on their guard and always look to buy from a reputable reseller.”

It is not the first time Microsoft has exhibited a tougher stance against rogue dealers this year. In August it snagged 11 for hard-disk loading or illegal software sales.