Cyan update problem in Lumia 520

[Unregistered]

Music is not working after cyan update in Lumia 520.even it is not highlited in the start screen i.e it is inactive.what should I do?

 

[Guytronic]

There are probably even more system or other apps not working also.

Recently had this same thing with a Lumia 521.
I backed up then hard reset then restored to get those apps not working to start properly.
Phone is now working...