This bug has been driving me nuts since I started using Xcode (4.6.3). Whenever I try to link a Storyboard item to my code, I get the error:
Could not
I was getting a similar problem, "Could not find a class named..." and the cause was stupid on my part once I figured it out. Make sure you aren't dragging from the item to the interface - make sure it's being dragged to the class itself