Microsoft chief executive Mr Steve Ballmer said last night he expects the final version of the Windows XP operating system will be finished this week.
Speaking at a technology conference in São Paulo, Mr Ballmer said he expected XP would be ready on Friday and that production of the new system could then start next Monday.
A spokesman at Microsoft headquarters in Redmond, Washington, would not comment on Mr Ballmer's statement but said Windows XP was on track for an October 25th retail launch.
Microsoft is eager to get Windows XP out because it is facing growing calls from rivals and privacy groups to change the product, which integrates new features such as instant messaging and online authorisation.
Microsoft shares rose 1.33 per cent to $62.7 yesterday.