You need to download and burn an iso image of Windows 8 or 8.1 depending on what your machine came installed with. Click Here for a good how to description the product keys are different for 8 and 8.1 so read the article carefully. If your machine is not bootable then you may have to do this on a different machine but your PC does have a DVD drive so you should be able to pur the new disc in and boot from it. The Windows key should be on the bottom of your laptop. Any missing files that sfc does not find should also be on the new disc that you have burned.
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