Upon boot up into Windows 7 Ultimate recently, suddenly Windows Explorer Library popped onto the desktop. I tried to search various forums for a solution in regedit but now find I can boot up to wallpaper where it hangs up. I am able to go to Windows Task Manager>New Task and type "C:WINDOWS/system32/userinit.exe" (without quotes) and the desktop boots. I don't know if I did something wrong in the registry editor. Is there a fix for this problem?