I would like to reinstall Windows 7 on my laptop https://www.asus.com/Laptops/K50IJ/ Intel® Pentium® Dual Core Processor T4200 : 2.20 GHz + 3GB RAM. I don't have the installation dvd. There's only a sticker on the back of the laptop with the product key on it. I was wondering if I could install the Windows 7 ISO files on a flash drive, then boot from it and perform a clean install of windows 7. I'm just worried it won't accept the product key for some reason. Then I'd be screwed. Will it work? Or is there a different method to reinstall windows 7 using the COA sticker without the dvd?