Microsoft on Monday announced that the head of its Windows unit is leaving in a management shake-up that comes just weeks after the release of a new generation of the computer operating software.

Windows president Steven Sinofsky will depart Microsoft and, effective immediately, his duties will be divided between a pair of executives who will answer directly to chief executive Steven Ballmer.

"I am grateful for the many years of work that Steven has contributed to the company," Ballmer said in a release.

"The products and services we have delivered to the market in the past few months mark the launch of a new era at Microsoft," he said.

"To continue this success it is imperative that we continue to drive alignment across all Microsoft teams, and have more integrated and rapid development cycles for our offerings."

Products launched in recent months include Windows 8, new Windows-powered mobile phones, a Surface tablet computer, and the "Halo 4" videogame for play on the company's Xbox 360 consoles.

Julie Larson-Green was promoted to lead Windows software and hardware engineering. Microsoft chief financial officer Tami Reller will run the business side of Windows in addition to her current duties.

"It is impossible to count the blessings I have received over my years at Microsoft," Sinofsky said in a written statement.

"I am humbled by the professionalism and generosity of everyone I have had the good fortune to work with at this awesome company."

Sinofsky joined Redmond, Washington-based Microsoft in 1989 as a software engineer and became head of the Windows team in 2009.

Microsoft kicked off sales of its revamped Windows 8 system and Surface tablet late last month as it ramped up efforts to compete in a market shifting rapidly from PCs to mobile devices.