Seinfeld booked to give Gates the last laugh

For two years, Microsoft has been prodded and poked fun of in Apple's "I'm a Mac, I'm a PC" ads on both sides of the Atlantic, and the company has finally snapped. In a last-ditch, and very expensive, attempt to fight humour with humour, the beleaguered software giant is paying the comic Jerry Seinfeld $10m (£5.3m) to appear in a massive new ad campaign of its own.

Television spots featuring the Seinfeld star kidding around with the Microsoft founder Bill Gates are ready to go live when the campaign starts next month, part of a $300m marketing blitz that will be the biggest in the company's history.

There's a simple aim: to stop Microsoft's troubled operating system Windows Vista from being a laughing stock. If the mooted slogan for the campaign is anything to go by – the rather clunky "Windows, not Walls" – Microsoft is going to be making heavy weather of it. And as news leaked yesterday, opinion was sharply divided about whether Seinfeld has the comic kudos to halt the advance of Apple, whose Macintosh, iPod and iPhone brands have become bywords for cool.

The 54-year-old, whose career was forged on the New York stand-up circuit in the 1980s, has been seen only rarely on TV since his much-loved sitcom ended a decade ago. But it is in perpetual reruns, and Seinfeld tours still wend their way through Manhattan to take tourists to the diners and apartment buildings featured in the show.

Microsoft's new ad agency, a little Miami outfit called Crispin Porter + Bogusky, which recently helped Burger King shed its fusty old image, believes that Seinfeld is still one of the best-loved celebrities in the US. And in any case, Microsoft would only have invited more derision if it went for a younger, more painfully cool star, such as Chris Rock.

"Microsoft will never be cool in the same way that Apple is cool," said Henry Blodget, the Silicon Valley blogger. "Companies with 90 per cent market share are almost never cool. Sorry, but nine out of 10 kids in the class can't be cool. The good news for Microsoft is that being cool has never been a part of its success formula. Microsoft's real problem, which has nothing to do with perception, is that its monopoly is eroding. Even Seinfeld won't be able to change that."

Microsoft has been fighting fires on all fronts. Windows Vista has been plagued with technical problems since its launch last year. Its traditional software business, maker of word-processing and other office software, is threatened by Google. And a multibillion-dollar attempt to dominate the Web with its MSN brand is making little headway, again because of Google. Even a tortuous, two-year attempt to buy Yahoo failed.

And Apple has been chipping at Microsoft's control of the personal computer market. Macintosh sales are up by two-fifths in the past year, thanks to ultra-sleek designs, more powerful microchips, the halo that the iPod has put round the company, and those pesky ads.

In a magazine interview last year, a furious Mr Gates accused Apple of spreading lies. "I don't know why it acting like it's superior. I don't even get it. What are they trying to say? Does honesty matter in these things, or if you're really cool, that means you get to be a lying person whenever you feel like it?"

The outburst exposed how "I'm a Mac, I'm a PC" had got under Microsoft's skin. With Seinfeld, maybe Mr Gates will get the last laugh.