Last night i installed windows 10. It took a while but in the end, it succeeded. Except for the icons in my desktop kept disappearing and appearing... I shut down my computer and when i started my pc this morning, it didn't work! I got the choice between restarting my pc or opening advanced settings. I tried to restart a few times but every time the screen with the choices came back. So i searched in the advanced settings what i could do and decided to downgrade back to W8.1, but after 6 hours it's still busy! Still the same blue screen that says "going back to previous version". What should i do?