To run the upgrade, you to already have installed Windows XP Service Pack 3, Windows Vista or Windows 7.

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According to the Microsoft Web site, the operating systems affected include Windows XP, Windows XP Service Pack 1, Windows 2000 SP2, Windows 2000 SP3 and Windows 2000 SP4.

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In its statement of objections, the Commission takes the preliminary view that Microsoft has failed to roll out the browser choice screen with its Windows 7 Service Pack 1, which was released in February 2011.

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Steven Levy (Newsweek) suggests that Google Pack helps Microsoft because it's basically a service pack for Windows.

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Steven Levy from Newsweek challenges Larry that Google Pack helps Microsoft because it's basically a service pack for Windows.

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It was relatively up-to-date, with the latest service pack for Windows Vista.

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Note: If you are running Windows NT, you need to have Service Pack 3 installed.

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The Mocbot worm attacks machines running Windows 2000 or XP that only have Service Pack 1 installed.

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In a legal filing made Tuesday evening with the U.S. District Court for the District of Columbia, Microsoft agreed to make three changes to Windows Vista when it offers an update to the software, dubbed Service Pack 1, later this year.

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The fact that Microsoft is not calling it Service Pack 1, and the way Microsoft is positioning and deploying Windows 8.1 is significant, though.

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