Hello, I know this is a simple answer, but I can't seem to find the solution. I created an object in its own class and I am trying to populate it with data from another class. For simple data types like NSString, I have no problem, but when trying make an NSMutableArray equal to another NSMutableArray or when I try to populate a NSMutableArray with another objects (like strings), I keep getting exception errors... Here is the object I am trying to populate: #import <Foundation/Foundation.h> @interface RSSFeedList : NSObject { NSString *subject; NSMutableArray *rssfeedDetail; } @property (nonatomic, retain) NSString *subject; @property (nonatomic, retain) NSMutableArray *rssfeedDetail; @end This is how I was able to populate the NSString 'subject' in another class: rssFeedList.subject = @"test"; However, if I follow similar convention within that same class with respect to an Array, it throws an exception: rssFeedList.rssfeedDetail = rssItemDetailArray; Where rssItemDetailArray is a NSMutableArray that I have built in the same class. I have also tried to add items (i tried strings for testing) to the NSMutableArray directly like so to no avail: [rssFeedList.rssfeedDetail addObject:@"test"]; Any ideas?? Thanks in advance!!