Using Swift I got the error that my \"TableViewController\" is unreachable because it has no entry points and no runtime access via [UIStoryboard instantiateViewControllerWithId
I fixed this by renaming the default "ViewController.swift" as "MainViewController.swift". Perhaps this is a warning to the user to insure everything is defined as you expect it to be.
I experienced this issue again and backtracked, eventually clearing the storyboard and then deleting it entirely from the project and the issue was still present. Relaunching Xcode fixed the issue.