When you first install and run Windows Vista, it will calculate your Windows Experience Index score to evaluate your computer's speed and graphics capabilities.
WEI has been a point of contention for many Windows Vista users because the WEI scores tend to be extremely low. Unfortunately, some software requires your WEI score to be above a certain threshold for all the features to work. Fortunately, it is easy to artificially raise your WEI score by modifying the configuration file.
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