iOS - Run Pausing when creating a scroll view

I am creating a scrollview in a separate tab in my app so that I can fit more controls on the screen. However, when I click on the tab, the run pauses with error:

Terminating app due to uncaught exception 'NSUnknownKeyExc开发者_如何转开发eption', reason: '[<UIViewController 0x5b20ff0> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key scroll.'

Any ideas why?

In your xib file you've connected something to a "scroll" property which doesn't exist anymore. Find this connection and remove it, and the error should go away.