Microsoft Monday said users testing Vista should abandon that effort for the Windows 7 RC candidate.
Bill Veghte, senior vice president for the Windows business, said during his keynote address at the annual TechEd Conference that Windows 7 RC should be the platform for users planning a client operating system migration.
Veghte said users that are already deploying Windows Vista, which first shipped in November 2006, should continue with those efforts. "Your investment will be protected, " he said, though he did not define what that protection entails.
Microsoft said last month that it will not drop Vista when Windows 7 ships, which is now planned for the "holiday shopping season."
Microsoft said it will continue at least until January 2011 selling Vista to computer makers, system builders, volume licensees and consumers, the company said.
There have been persistent rumours that Microsoft would abandon Vista once Windows 7 ships. Vista has not sold well in the enterprise since it shipped.
Forrester Research recently reported that Vista's business penetration is still in single digits at 9%. The company predicts that number could hit 30% before year-end.
Monday's recommendation for Vista testers to switch to Window 7 RC could cause that number to drop substantially.
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