I need help! My laptop log in disappeared leaving nothing but wallpaper?

I have a big problem! When I turn on my Dell Inspiron, it loads and everything and when it gets to the part where you click your user profile and log in, nothing is their. Like My profile isn't their its just completely blank. But the background is still their its like blue and green or something. The cursor moves but no buttons worked. Iv tried to open task manager and when the computer boots up iv tried safe mode and system restore and repair, but it just always ends up booting to this blank login screen with the background. If anyone knows how to fix this please let me know, thanks.