A new, free browser that claims it can safeguard privacy has been hit with accusations that it is really a platform for advertising and - worse still - is insecure.

Released last week, Browzar is not an independent browser but an Internet Explorer (IE) shell download that its creators have promoted as a way for ordinary Internet users to visit websites and run searches without leaving traces of their activity - browsing history, auto-complete forms, and cookies - behind them as with a conventional browser. These elements are all said to be securely deleted by the software.

Now posters to a number of technical discussions groups, including Web3.0log.org, have taken issue with some of the program’s alleged features. They accuse it of being little more than an advertising platform masquerading as a security add-on.

According to posters, anyone using it found that the Browzar homepage had become their default homepage, a setting that could not be adjusted. Moreover, because this homepage used the controversial Overture Internet search engine, paid-for advertising was being returned for any search ahead of unpaid results in a way that would be difficult to detect.

"There was time when badware developers tried to install ad pages as homepage or searchpage in user’s IE by any possible means. Nowadays users install adware voluntarily and write news about it. True web2.0 style," said one poster to the discussion group.

Posters also accused the software of failing to carry out its claimed security functions to a high standard. One blogger claimed the program would allow anyone who knew where to look on a PC to restore browsing history, cookies, and other temporary Internet files.

The man behind Browzar, Ajaz Ahmed, rejected the criticisms, pointing out that the program was still in its beta phase and that his company was currently considering ditching the Overture search engine after the negative comments.

When Techworld tested the search feature on version 1.2.0 0, the engine returned results based on the separate Ask engine, so it appears the company has already reacted to the slating of Overture. Ask makes a more obvious separation between sponsored links and unpaid results, and so could head off the criticism of Browzar that its commercial bias was not easy to detect.

According to Ahmed, the program’s security design had also been completely misunderstood. "This is aimed at people who want to supplement their normal browser when they want privacy," he said. "We haven’t targeted the more technical users out there."

Because the software worked as a lightweight shell add-on to IE, and was a small download, it could be removed from a PC simply by deleting its desktop icon. Users could download it and remote it every time they used a public computer, he suggested. Although the program defaulted to the Browzar homepage, it was still possible to use other search engines such as Google.

Ahmed said that the shell was given away free of charge, which allowed the company to make money on a click-through basis from search results. The company had further unnamed products in its development pipeline.

Ahmed is notable for being one of the brains behind Freeserve, the first UK ISP to offer free Internet access when it was set up in the late 1990s. It grew to become the largest Internet provider in the country, and was later sold by its parent company to France Telecom.