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How to upgrade from windows xp to windows 7 
Contact your computer manufacturer to see if your system is able to run windows 7. 
This step is important because some windows xp systems are not compatible with windows 7. If you have a custom built pc, make sure you have the correct hardware requirements before you upgrade.
Run the microsoft compatibility checker, which can be downloaded for free at microsoft.com. If your system does not meet the minimum requirements, do not upgrade to windows 7 and consider buying a new pc.