Windows Vista of January 2009, it had been announced that Vista usage had surpassed Microsoft's pre-launch two-year-out expectations of achieving 200 million users. At the release of Windows 7 (October 2009), Windows Vista (with approximately 400 million Internet users) was the second most widely used operating system on the Internet with an approximately 19% market share, the most widely used being Windows XP with an approximately 63% market share. In May 2010, Windows Vista's market share had an estimated range from 15% to 26%. On October 22, 2010, Microsoft ceased sales of retail copies of Windows Vista, and the OEM sales for
Microsoft Windows version history for the operating system), and in theory prevented them from inadvertently corrupting the memory space of other Win32 applications. In this respect the functionality of Windows 95 moved closer to Windows NT, although Windows 95/98/ME did not support more than 512 megabytes of physical RAM without obscure system tweaks. IBM continued to market OS/2, producing later versions in OS/2 3.0 and 4.0 (also called Warp). Responding to complaints about OS/2 2.0's high demands on computer hardware, version 3.0 was significantly optimized both for speed and size. Before Windows 95 was released, OS/2 Warp 3.0 was even shipped preinstalled with several