When trying to run my project I get this error and I don´t know what it means :
_OBJC_CLASS_$_MyWindowController", referenced from: objc-class-ref in AppDelegate.
ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation)
What does it mean and how can I get rid of it?
Any ideas?