Head of Microsoft's Windows unit steps down Mon Nov 12, 2012 9:39pm EST (Reuters) - Microsoft Corp said the head of its flagship Windows division and the driving force behind Windows 8, Steven Sinofsky, will be leaving the company with immediate effect, days after the software giant launched the Surface tablet. Sinofsky, who presented at the launch of the Windows 8 operating system in New York City last month, will be succeeded by Julie Larson-Green, who will head the Windows hardware and software division, the company said in a statement. Tami Reller will remain 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, Microsoft said. At the launch event in October, Sinofsky and his team showed off a range of devices running Windows 8 from PC makers such as Lenovo Group Ltd and Acer Inc, but devoted most of their energy to the second half of the presentation and the Surface tablet, the first computer Microsoft has made itself. Reporting by Sakthi Prasad and Nicola Leske; Editing by Edmund Klamann