Windows 7 (formerly codenamed Blackcomb and Vienna) is the next version of Microsoft Windows and the successor to Windows Vista Microsoft has stated that it is "scoping Windows 7 development to a three-year timeframe", and that "the specific release date will ultimately be determined by meeting the quality bar." Windows 7 will ship in both client and server versions with the client versions available in both 32-bit and 64-bit editions. The server version of Windows 7, Windows Server 2008 R2, is 64-bit only.
Although for a long period of time Microsoft maintained a "translucency" policy (rather than a "transparency" policy) in the lead up to the PDC, or Professional Developer's Conference, the Windows 7 project, features and technologies are slowly being revealed. Public presentations from company officials have disseminated information about some features and leaked information from people to whom the Milestone builds (M1, M2 and M3) of Windows 7 were provided also provides some insight into the feature set.
In 2000 Microsoft started the planning to follow up Windows XP and its server counterpart Windows Server 2003 (both codenamed Whistler) with a major new release of Windows that was codenamed Blackcomb (both codenames refer to the Whistler-Blackcomb resort). This new version was at that time scheduled for a 2005 release.
Major features were planned for Blackcomb, including an emphasis on searching and querying data and an advanced storage system named WinFS to enable such scenarios. In this context, a feature mentioned by Microsoft co-founder Bill Gates for Blackcomb was "a pervasive typing line that will recognize the sentence that [the user is] typing in."
Later, Blackcomb was delayed and an interim, minor release, codenamed "Longhorn", was announced for a 2003 release. By the middle of 2003, however, Longhorn had acquired some of the features originally intended for Blackcomb, including WinFS, the Desktop Window Manager, and new versions of system components built on the .NEt Framework. After the 2003 "Summer of Worms", where three major viruses − Blaster, Sobig, and Welchia − exploited flaws in Windows operating systems within a short time period, Microsoft changed its development priorities, putting some of Longhorn's major development work on hold in order to develop new service packs for Windows XP and Windows Server 2003 that included a number of new security and safety features. Development of Longhorn was also "reset" in September 2004 (see Mid-2004 to Mid-2005: Development "reset") as a result of concerns about the quality of code that was being introduced to the operating system. The eventual result of this was that WinFS, the Next Generation Secure Computing Base, and other features seen in some of the Longhorn builds were deemed "not ready" for wide release and as such did not appear in Longhorn when it was released as Windows Vista and Windows Server 2008.
As major feature work on Windows Vista wound down in early 2006, Blackcomb was renamed