Tami Reller, finance and marketing head of the Windows business, did not give a precise comparison, but sales of 40 million licenses for Windows 8, launched on October 26, appear to be ahead of Windows 7, which sold just over 60 million units in the first 10 weeks on sale at the end of 2009. The sales number represents a solid but unspectacular start for the touch-friendly operating system designed to combat Apple Inc’s and Google Inc’s domination of mobile computing, which has shunted aside PCs in favor of iPads and smartphones.

A Microsoft Surface tablet PC is displayed on a stand during its launch event with Microsoft Windows 8 in New York October 25, 2012.