Possible Duplicate:
NSLayoutConstraint crashes ViewController
recently after updating Xcode my app now fails to load brining up this unhanded exception of which i dont know where this has come from now if anyone could share some light or even a fix for this would be great
int retVal = UIApplicationMain(argc, argv, nil, nil);
*Terminating app due to uncaught exception ‘NSInvalidUnarchiveOperationException’, reason: ‘Could not instantiate class named NSLayoutConstraint’
First throw call stack:
(0x15b1022 0x13a0cd6 0x1559a48 0x15599b9 0x9ba4a3 0x9ba67b 0x9ba383 0x8ba16d 0x8bbeb7 0x698ce1 0x698ff8 0x69817f 0x6a7183 0x6a7c38 0x69b634 0x2d1def5 0x1585195 0x14e9ff2 0x14e88da 0x14e7d84 0x14e7c9b 0x697c65 0x699626 0x2b1d 0x2a55 0x1)
terminate called throwing an exception(lldb) *
Have you created a Xib which is using the new auto-layout added in iOS 6? By default xCode now makes Xib files use auto layout. You can turn auto layout off in your xib by un-checking a box in the xib file inspector.