Hi, I am using OSX 10.6.4 and MAcRuby 0.6. I created a new project and just simply added to the MainWindow.nib an Image browser an then built When Running the project in Xcode I get a SIGABRT.... So I ended up looking in a console what happened... AndI get the following error message Any idea what I am missing or doing wrong? uncaught Objective-C/C++ exception... 2010-08-15 11:54:20.089 iWarranty[55002:903] An uncaught exception was raised 2010-08-15 11:54:20.091 iWarranty[55002:903] *** -[NSKeyedUnarchiver decodeObjectForKey:]: cannot decode object of class (IKImageBrowserView) 2010-08-15 11:54:20.093 iWarranty[55002:903] *** Terminating app due to uncaught exception 'NSInvalidUnarchiveOperationException', reason: '*** -[NSKeyedUnarchiver decodeObjectForKey:]: cannot decode object of class (IKImageBrowserView)' *** Call stack at first throw: ( 0 CoreFoundation 0x00007fff863edcc4 __exceptionPreprocess + 180 1 libobjc.A.dylib 0x00007fff823ff0f3 objc_exception_throw + 45 2 CoreFoundation 0x00007fff863edae7 +[NSException raise:format:arguments:] + 103 3 CoreFoundation 0x00007fff863eda74 +[NSException raise:format:] + 148 4 Foundation 0x00007fff8558ea86 _decodeObjectBinary + 2427 5 Foundation 0x00007fff8558f805 -[NSKeyedUnarchiver _decodeArrayOfObjectsForKey:] + 1229 6 Foundation 0x00007fff8558fd45 -[NSArray(NSArray) initWithCoder:] + 462 7 Foundation 0x00007fff8558eaff _decodeObjectBinary + 2548 8 Foundation 0x00007fff8558df79 _decodeObject + 208 9 AppKit 0x00007fff8833a47a -[NSView initWithCoder:] + 362 10 Foundation 0x00007fff8558eaff _decodeObjectBinary + 2548 11 Foundation 0x00007fff8558df79 _decodeObject + 208 12 AppKit 0x00007fff8834883b -[NSWindowTemplate initWithCoder:] + 3824 13 Foundation 0x00007fff8558eaff _decodeObjectBinary + 2548 14 Foundation 0x00007fff8558f805 -[NSKeyedUnarchiver _decodeArrayOfObjectsForKey:] + 1229 15 Foundation 0x00007fff8558f248 -[NSSet(NSSet) initWithCoder:] + 447 16 Foundation 0x00007fff8558eaff _decodeObjectBinary + 2548 17 Foundation 0x00007fff8558df79 _decodeObject + 208 18 AppKit 0x00007fff882ca55a -[NSIBObjectData initWithCoder:] + 1983 19 Foundation 0x00007fff8558eaff _decodeObjectBinary + 2548 20 Foundation 0x00007fff8558df79 _decodeObject + 208 21 AppKit 0x00007fff882c9c89 loadNib + 146 22 AppKit 0x00007fff882c91e9 +[NSBundle(NSNibLoading) _loadNibFile:nameTable:withZone:ownerBundle:] + 248 23 AppKit 0x00007fff882c9021 +[NSBundle(NSNibLoading) loadNibNamed:owner:] + 326 24 AppKit 0x00007fff882c65a3 NSApplicationMain + 279 25 ??? 0x0000000101201300 0x0 + 4313846528 26 libmacruby.dylib 0x000000010013d81a rb_vm_dispatch + 3450 27 ??? 0x0000000101200630 0x0 + 4313843248 28 libmacruby.dylib 0x000000010014f9ac rb_vm_run + 348 29 libmacruby.dylib 0x00000001000431e9 ruby_run_node + 73 30 libmacruby.dylib 0x000000010014fcb8 macruby_main + 360 31 iWarranty 0x0000000100000eaf main + 40 32 iWarranty 0x0000000100000d20 start + 52 ) terminate called after throwing an instance of 'NSException' Abort trap Thanks Emmanuel