Win7 system wallpaper disappears the desktop becomes black how to do?

            Analysis of the cause of the failure:
may be caused by the prohibition of related services, as long as the service is turned on to solve the problem.
Solution:
1. Enter services.msc in the start menu and open it. Set the status of the three services Sever, Software Protection and SPP Notification Service to "Started", restart the computer;
2, or, open the control panel - management tools - services - look at the three services Sever, Software Protection, SPP Notification Service are open, if not, the startup type is all set to "automatic" Right click on "Properties" to change).
The above is the two ways to solve the problem that the win7 wallpaper disappears into a black desktop. After setting, the desktop wallpaper is restored. Everything is normal. Friends who have the same problem can follow the above methods.