Failed to find a blueprint implementable while calling in c++

[Roy_Wierer.Seda145]

Sounds like a corrupt reference to me:

UFunction* UObject::FindFunctionChecked( FName InName ) const
{
	UFunction* Result = FindFunction(InName);
	if (Result == NULL)
	{
		UE_LOG(LogScriptCore, Fatal, TEXT("Failed to find function %s in %s"), *InName.ToString(), *GetFullName());
	}
	return Result;
}

When / where do you get this error? It might be a broken blueprint node referencing a deleted / broken / renamed function.