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No reason was given for the sudden resignation, which the company was presenting as a mutual decision. Coming a couple of weeks after the official launch of Windows 8, however, it clearly wasn't the best timing.
"I am grateful for the many years of work that Steven has contributed to the company,” CEO Steve Ballmer said in a statement. "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."
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Sinofsky, above, who in looks and style bears more than a passing resemblance to Amazon founder Jeff Bezos, was formerly one of the most trusted members of Ballmer's inner circle. When the Microsoft Surface Tablet was unveiled at a press event in June, it was Sinofsky who led the charge (and who was an unfortunate victim of a tech glitch where the tablet crashed, as captured in this video).
Ballmer admitted this weekend that early sales of the Surface tablet were "modest."
According to AllThingsD, sources inside Microsoft are comparing Sinofsky's departure to that of Scott Forstall from Apple. Both, apparently, were strong-willed executives who didn't get on well with their teams.
In Sinofsky's case, Ballmer's statement suggests that this was holding back the speed of Windows' development. Indeed, he'll be succeeded by not one but two executives: Julie Larson-Green on the engineering side of Windows, and Tami Reller, formerly the division CFO, on the business side.
A former engineer who rose through the ranks of the Office team at Microsoft, Sinofsky has been heading up the Windows division since 2009. He headed up development of both Windows 7 and 8 after the disaster that was Vista.
BONUS: Sinofsky's Surface Launch
Windows Chief Steve Sinofsky
Sinofsky demonstrates just how easy it is to watch video hands-free with the Surface's kickstand.
This story originally published on Mashable here.