Windows Longhorn

Windows Longhorn is an operating system produced by Microsoft as a member of the Windows NT family of operating systems for use on personal computers. Development was completed on November 8, 2004, and over the following three months, it was released in stages to computer hardware and software manufacturers, business customers and retail channels. On January 30, 2004, it was released worldwide and was made available for purchase and download from the Windows Marketplace; it is the first release of Windows to be made available through a digital distribution platform. The release of Windows Longhorn came more than five years after the introduction of its predecessor, Windows Whistler the longest time span between successive releases of Microsoft Windows desktop operating systems.

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