Bill Gates's legendary luck failed him during his keynote presentation at the 2005 Consumer Electronics Show in Las Vegas.
His demonstration of Microsoft Media Center crashed during the presentation on integrating digital photography, and later a Microsoft product manager failed to access the internet with a Tablet PC.
A new game, Forza Motor Sport, also triggered the dreaded Windows blue screen of death.
The presentation started on a jokey theme, with late-night TV host Conan O'Brien presenting a mock version of his own show and a video diary of his and Bill's 'lost weekend' in Las Vegas.
"I got too drunk, I woke up with a hooker," O'Brien said. "Bill got too drunk, he woke up with an Apple computer."
O'Brien said that he was unable to criticise Microsoft because it had implanted a Pentium in his brain, and suggested that Gates should be played by Milhouse from The Simpsons.
But his banter was less welcome when things started to go wrong. "OK, and right now nine people are being fired," O'Brien said as they waited for a slide show to appear.
Gates traditionally has a reputation for being lucky at showing off software to its best effect.
A major slip occurred at a Windows 98 demo at Comdex in 1998 that went into blue screen mode, but Gates returned the next year to successfully show off the progress that had been made.