Accidentally pressed reset app preferences

[Saisupreeth1997]

When i open my camera.A message coming that this app is using by another application,close it.
Or reboot ur device and try it.

 

[N4Newbie]

Reset app preferences should not cause that error. However, I have seen that error when a flashlight app has not properly released the camera's flash.

Did you reboot? Do you still get the error?