Microsoft failed to ease fears last night that a new version of its Windows software system would be further delayed.
"We will ship Windows Vista when it is available," Kevin Johnson, co-president of Microsoft's platforms and services unit, said at the company's annual financial analysts' meeting.
This uncertainty over when Microsoft and the rest of the industry would benefit from the surge in revenue growth that typically accompanies a major Windows upgrade led Microsoft's shares to close down 2 per cent at $23.87 on the Nasdaq last night.
Windows sits on more than 90 per cent of the world's personal computers.
Windows Vista, already five years in the making, has been postponed by Microsoft several times. Quality assurance delays have put off the consumer version of Windows until early 2007 - after the crucial holiday shopping season.
Vista is set to ship to corporate customers this November.
Goldman Sachs analyst Rick Sherlund said the cautious comments represent a delayed confirmation of his thesis that Microsoft would not begin to see revenue from the general availability of Windows Vista until March or April 2007.
Microsoft last week forecast revenue for the fiscal year ending in June 2007 to grow 12 per cent to 14 per cent, to between $49.7 billion and $50.7 billion.
Microsoft forecast another year of losses at its mobile phone, games and devices business before turning a profit in the business year ending June 30th, 2008.