Tell us the brand, model, and age of the computer.
Tell us what happens that results in: " it ends up with me re formatting it and losing all valuable data..."
What hardware have you installed since buying the computer?
Are you installing Service Pack 2 from a disc, or from a download from Microsoft?
If you are not using the Microsoft install disc, order it from Microsoft. I believe the cost is still free with $3.95 shipping and takes just a couple of days... but the rate may be higher when postage goes up tomorrow.
It is most likely some hardware component that has nothing to do with Service Pack 2, but many HP, Compaq, Gateway, and Dell units built before Service Pack 2 was released have had issues, including shutdowns, after Service Pack 2.
In those cases, the manufacturer placed new drivers for each model on their website. You will want to reinstall all drivers, chipsets, and other software from the website that is more recent than the date of purchase of your computer.
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