I tried to install 2 different DVD's of the Vista Upagrade in place of XP and after 23 hours with phone assistance from Microsoft technicians we did not succeed. Main reason was that Microsoft did not accept the Product Key of either DVD. It also was not compatible with HP/Compaq sound drivers and they were not able to resolve that issue and did not accept some of other companies software, either. Some of their employees said that Microsoft would not reimburse me for their faulty DVD's.

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