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
Security and safety features new to Windows Vista ensures that the computer running Windows Vista starts in a known-good state, and it also protects data from unauthorized access. Data on the volume is encrypted with a Full Volume Encryption Key (FVEK), which is further encrypted with a Volume Master Key (VMK) and stored on the disk itself. Windows Vista is the first Microsoft Windows operating system to offer native support for the TPM 1.2 by providing a set of APIs, commands, classes, and services for the use and management of the TPM. A new system service, referred to as TPM Base Services, enables the access to and sharing