If you get a PC running Windows 7 but can't divorce yourself from Windows XP, Microsoft will give you 18 months to downgrade - not six.

That's the line from Microsoft, which said that downgrade rights will be available from the date Windows 7 ships - October 22, 2009 - to April 1, 2011.

Organizations with Windows volume license, which cover 250 PCs or more, will be able to downgrade to any prior version of Windows - a standard policy.

But the downgrade window will expire before 18 months if a service pack ships. Downgrade rights to Windows Vista will not expire.

Microsoft confirmed the stance for The Reg in the wake of a report by Redmond Channel Partner.

That came after long-time Microsoft watcher Michael Silver of Gartner was said the company had discussed a six-month limit on downgrades from Windows 7 with him "multiple times and characterized it to him as a 'public' policy'." ®

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