Windows and Windows Live president Steven Sinofsky has left Microsoft, with Julie Larson-Green promoted to lead all Windows software and hardware engineering.

In a leadership shake-up at the software giant, Tami Reller retains her roles as chief financial officer and chief marketing officer and will assume responsibility for the business of Windows.

Both executives will report directly to Microsoft CEO Steve Ballmer as part of the changes.

“I am grateful for the many years of work that Steven has contributed to the company,” Ballmer says.

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

"We’ve built an incredible foundation with new releases of Microsoft Office, Windows 8, Windows Phone 8, Microsoft Surface, Windows Server 2012 and ‘Halo 4,’ and great integration of services such as Bing, Skype and Xbox across all our products.

"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.”

Effective immediately, Sinofsky did not give anything away through his parting statement, saying only:

“It is impossible to count the blessings I have received over my years at Microsoft.

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

Sinofsky's replacement Larson-Green has worked on and led some of the most successful products for Microsoft since 1993, including the user experiences for early versions of Internet Explorer.

For Windows 7 and Windows 8 she was responsible for program management, user interface design and research, as well as development of all international releases.

“Leading Windows engineering is an incredible challenge and opportunity," Ballmer says of Larson-Green.

"And as I looked at the technical and business skills required to continue our Windows trajectory — great communication skills, a proven ability to work across product groups, strong design, deep technical expertise, and a history of anticipating and meeting customer needs — it was clear to me that Julie is the best possible person for this job, and I’m excited to have her in this role."

Joining Windows in 2007 from the Microsoft Dynamics Division , Reller's will now drive business and marketing strategy for Windows devices, including Surface and partner devices, in addition to her current marketing and finance responsibilities.

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