Microsoft launched Windows 7 in October last year
Microsoft has reported a 60% jump in profit, thanks largely to "exceptional demand" for Windows 7.
Net profit came in at $6.66bn (£4.13bn) for the three months to 31 December 2009, up from the $4.18bn it made in the same period a year earlier.
It also reported record revenues of $19.2bn, which comfortably beat analysts' forecasts.
"We are thrilled by the consumer reception to Windows 7," said Kevin Turner, chief operating officer.
"This is a record quarter for Windows units."
Microsoft released Windows 7 in October last year.
Windows 7 has proved to be Microsoft's best-selling operating system to date after the disappointing Vista.
Microsoft was helped by a rebound in personal computer sales in the run-up to Christmas.
The company's results are closely tied to computer sales because its two most profitable divisions make the Windows Operating System and Office business software.
"These are outstanding numbers," said Brendan Barnicle from Pacific Crest Securities.
"The upside was in the Windows business and service and tools, and Office business. The online business came in line and the only business shy of expectations was Xbox."
Shares in Microsoft rose 25 cents, or 0.9%, to $29.41 in after-hours trading.
The company did not make any specific profit or sales forecasts, after making the decision to stop doing so in January 2009, citing market volatility.
Microsoft is the latest technology company to report earnings results.
Yahoo and Apple both announced higher profits earlier this week, while Google reported strong figures last week.
However, Nintendo saw a near 10% fall in profits after a slowdown in sales of its Wii games console.