Windows Vista and Office 2007 sales helped Microsoft build revenue 32 per cent year-on-year the company said last night.

Microsoft achieved $14.4 billion in revenue for its March quarter, exceeding expectation. The company had anticipated between $13.89 billion to $14 billion in revenue in the quarter, it earned $10.9 billion in the year-ago quarter.

The company did say that the delayed release of Vista had meant it was able to defer $1.67 billion of Vista sales revenue from its fiscal second quarter to its third quarter which ended March 31.

These Vista sales were deferred into the quarter in order to account for discounted upgrades given to PC buyers.

Vista revenue will continue to play a key role in Microsoft's client business though fiscal 2008, Microsoft chief financial officer Chris Liddell said.

The company predicts the percentage breakdown between sale revenue from Vista and Windows XP will be 85 per cent to 15 per cent in that time frame. "Obviously, the faster the transition to Vista, the bigger and more positive the impact will be in '08," Liddell said.

Microsoft continued its conservative trend for its fiscal fourth quarter guidance. The company expects revenue in the range of $13.1 billion to $13.4 billion for the quarter, which ends 30 June.

Looking to its next fiscal year, which ends 30 June, 2008, Microsoft expects revenue in the range of $56.5 billion to $57.5 billion.

Comparing the results to Apple's Mac sales growth in the March quarter, Jupiter Research analyst Michael Gartenberg asked: "If Apple was able to demonstrate growth of Mac sales during the quarter when Microsoft did its largest Windows launch, what does this say about the way consumers are thinking about Vista?"

Elizabeth Montalbano contributed to this report.