The next version of Windows – Windows 7 – will be available in 18 months, according to a letter company senior vice president Bill Veghte has sent to Microsoft customers.

Veghte said Windows 7 will become available three years after Windows Vista became widely available, thus setting the target release date for the new operating system as January 2010.

The letter - titled 'An Update on the Windows Roadmap' - told customers: "You have told us you want a more regular, predictable Windows release schedule", following the 5-year gap between the release of XP and Vista.

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Veghte also said Microsoft had learned from the application compatibility problems customers have experienced with Vista, promising the migration process between Vista and Windows 7 will be "straightforward".

"You've also let us know you don't want to face the kinds of incompatibility challenges with the next version of Windows you might have experienced early with Windows Vista. As a result, our approach with Windows 7 is to build off the same core architecture as Windows Vista so the investments you and our partners have made in Windows Vista will continue to pay off with Windows 7."

Veghte's discussion of Windows 7 was part of an effort to clarify the June 30 XP deadline that will see the operating system removed from retail shelves and OEM hardware, and to tout the virtues of Windows Vista.

See also:

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See the latest news on Microsoft's next desktop operating system in our Windows 7 spotlight