To many employees, Vista, the Windows update, exemplifies the company's struggles. When the project was conceived half a decade ago, it was envisioned as a breakthrough: an operating system that would transform the way users store and retrieve information. But the more revolutionary features have been dropped, and Vista will arrive three years after researcher Gartner Inc. originally predicted that it would ship. Worse yet, they say, nobody has been held accountable. 'People look around and say: 'What are those clowns doing?'' says Adam Barr, a program manager in the Windows group.