How to delete music libary when window does not appears from llibary

[Mixnetwork]

Its strange but if i click on music libary the window does not open.
in the tasklist is see he opnened the libary but when i click on it nothing happens.
Strange thins is in the searchfield (schreenshot) he shows all songs.
Is there a way to delete all libaries per commandline?
I do not know what else to do.

 

[Mixnetwork]

I lready solved it by importing an older backup file , now it works again