I recently downloaded Windows 10 for my PC. It worked fine for a couple of days, but then it just stopped working. It boots up with the HP logo and the spinning wheel, loads for a while, then the logo disappears like it normally does. But, instead of launching into the login screen, it shows a black screen alternating to grey. I tried start up repair, and followed all the instructions I could find about sfc scans, but it doesn't work. The sfc scans show a verification load, that reaches 100%. Then it says "Windows resource protection could not perform the requested operation." The only other fixes I could find required downloads or windows disks. I upgraded windows online, so I don't have one, and I'm a total noob at software, I only know hardware, so I have no idea how to do online searches from outside windows. Thanks in advance for your help!