why Xcode 7.2 crash 'Could not instantiate class named IBNSLayoutConstraint'?

*** Terminating app due to uncaught exception 'NSInvalidUnarchiveOperationException', reason: 'Could not instantiate class named IBNSLayoutConstraint'

I just update Xcode to 7.2 then i start to check is everything alright. but I have this error and it crashes. I dig this problem, everybody said that "Make sure you don't have any constraints installed for views that aren't installed." but I don't have any uninstalled constrains. and I don't have any NSLayoutConstraint outlets. Thanks a lot.

You probably using InterfaceBuilder Storyboard for localization. You should also consider them and remove inactive constraits inside them or use Localizable Strings for localization.

You can also check this answer.