My HP laptop will open up and all fine, but if I hit the Windows start button on my screen or my keyboard it will NOT open. It also will not allow me to use Cortana. I have tried tutorials from others with the same issue but none of them seem to work for me, despite my many attempts, unless I am doing something wrong. I can usually open up things on my taskbar, thus allowing me to access the internet, but even that malfunctions from time to time, and I haven't been able to open up the mail app or app store, only my browsers. If I could get some help i'd really appreciate it as it is getting quite tedious, thanks!