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Microsoft's newly released Service Pack 1 may solve some of the performance glitches that have annoyed Windows Vista users and discouraged others from adopting the OS, but it doesn't appear from our initial tests to be a panacea. In our first tests of the service pack, file copying, one of the main performance-related complaints from Vista users, was significantly faster. But other tests showed little improvement and in two tests, our experience was actually a little better without the service pack installed than with it.