from when you did the upgrade here is how.
http://www.pcworld.com/article/2960692/windows/how-to-uninstall-windows-10-and-go-back-to-windows-7-or-8.html
If you are longer then 30 days you need to use your Windows 7 system restore disks (I knwo you create the first time you ran the computer) or if you have the retail version use the disk you received in your retail package.
I had win7 and upgraded to win10. HOW do I go back to win7 ???

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