I downloaded the free version of Windows 10 from Microsoft. After it downloaded, I received a notice from Norton that my present internat security is not compatible with Windows 10. The box asked me to click a button to download the Windows 10 compatible version of Norton. After doing so, my computer will not function. All it does is flash my computer background off and on and will not even allow me to use the start button. Something is very wrong. I have an HP computer. The computer I am using now is a small spare device I have. My main computer will not work!!! After I log on to Windows 10, it malfunctions.