A company set up by Conservative Party chairman Grant Shapps is being investigated by the advertising watchdog over claims that its website misled users.
The Advertising Standards Authority (ASA) said it was studying a complaint about the HowToCorp website, which used to be run by Mr Shapps, featuring get-rich-quick advice from supposedly successful businessmen Sebastian Fox and Michael Green.
Green - a name that has been used by Mr Shapps as a business alias - is presented as having built up a 28 million US dollar fortune. The website, which is no longer active, invited users to pay a fee to benefit from his advice.
The ASA has received a complaint suggesting neither Green nor Fox are real people and questioning whether testimonials on the site were genuine.
A spokesman said: "We have received a complaint about a website which is headed 'Sebastian Fox's How To Corp - The Home of Great Toolkits on the Net', and which includes links to articles on each advertised toolkit which it says are written by Michael Green. The website also includes links to testimonials.
"The complainant has challenged whether the website is misleading, because it implies Sebastian Fox and Michael Green are successful businessmen whereas they believe neither are real people, and whether the testimonials are genuine. We have launched an investigation to establish whether there is a problem under the Advertising Code."
A Conservative Party spokesman said Mr Shapps had not been involved with the company for four-and-a-half years. The spokesman added: "These websites are no longer online and any blogger can make a spurious complaint about any website, which then has to be investigated. This is in the hands of the ASA."
Last weekend, Mr Shapps was forced to insist he was not living a double life as his business alter ego came under scrutiny. The senior Tory said it was normal practice to use a pen name after pictures emerged of him attending an internet conference, shortly before he was elected to Parliament, wearing a "Michael Green" name badge.
It sparked claims by Labour MP Steve McCabe that Mr Shapps had "multiple personalities and questionable business practices" while Lord Prescott dubbed him "two tags" - a reference to his own nickname of "two Jags".
Mr Shapps said: "Before I went into Parliament, I used to write business publications and, like many authors, wrote under a business name. I was always very open about it and I actually went to one conference, where that picture was from, it was sort of open fact. It was in my biography, it was in the conference programme."