More than one in ten (11 percent) of Brits have purchased pirated software, says Microsoft.

According to the tech giant, nearly a third (31 percent) of those in possession of counterfeited programs were not aware the software was pirated.

Microsoft's latest OS, Windows 7, and the DVD of Harry Potter and the Deathly Hallows were named at the most popular pirated items.

Furthermore, more than two thirds (68 percent) of Brits revealed they are considering buying counterfeit software in a bid to save money. Men are 20 percent more likely than women to knowing purchase counterfeit goods, and 15 percent more likely to buy pirated programs in a bid to save money.

"For years, British consumers have been ripped off by dodgy dealers selling counterfeit software. This trend is set to continue if we don't raise awareness of the increasingly sophisticated methods employed by the counterfeiters," said Michala Wardell, head of anti-piracy at Microsoft.

"Over the past 18 months, counterfeiters have changed tack: we're now seeing more pirated products being advertised at higher prices. These higher price points, whilst still highly discounted, appear more realistic to consumers seeking out a Christmas bargain."

Wardell said that, unlike a pirated DVD or counterfeit handbag, the negative effects of counterfeit software are far greater: "People are opening themselves up to a host of problems such as identity theft and data loss. These are serious issues and it's absolutely vital that consumers are on the look-out and checking before they buy."

Microsoft urged web users who stumble across pirated software to report it to [email protected] More advice on how to distinguish pirated software from the real deal can be found at Microsoft's dedicated site.

See also: More than a quarter of UK software is unlicensed or pirated