My computer loads normally to the login screen. I enter my password and press enter. It displays the welcome message with the spinning circle thing, and seems to load correctly. When finished, it is at this point my screen goes black showing only the cursor which I can move. When I hover over where the taskbar should be, the screen dims a bit. When I move away from the 'invisible' taskbar, the screen brightens to it's original state. This leads me to believe that the desktop may be loaded, but for some reason is not displaying. After about a minute, everything displays and the computer works perfectly. Occasionally, there is not an issue, and the desktop loads perfectly, seconds after logging in.
Session "Microsoft Security Client OOBE" stopped due to the following error: 0xC000000D
The VirtualRouterService service hung on starting.
Event filter with query "SELECT * FROM __InstanceModificationEvent WITHIN 60 WHERE TargetInstance ISA "Win32_Processor" AND TargetInstance.LoadPercentage > 99" could not be reactivated in namespace "//./root/CIMV2" because of error 0x80041003. Events cannot be delivered through this filter until the problem is corrected.
I was experiencing the same problem when I still had avast antivirus software installed. I uninstalled it since the windows defender is already an antivirus software in windows 8. since then I never happened again.