Debug Error on iOS

I am new to iPhone development.

My app is working fine but after using it for some time and performing all the functionality sometimes a view does not open. The view contains the custom cell which contain a UIImageView and UILabel and UIImageView After using the app for long time the cell only shows the UILabel and click on cell it shows

Debugger Error Contain some invalid hexadecimal

When clicking on cell the next which is suppose to open it shows an exception

NSInvalidArgumentException', reason: '-[UIViewController _loadViewFromNibNamed:bundle:] was unable to load a nib named "Frie开发者_运维问答ndShoppingListViewController"`

I think you are fetching image from network. you rename some file outside xcode? reassigned imageView property or you can delete controller and drag an drop another and make all connection. or you can rework from last back-up point.