I just need some understanding here. I use this journal app called Day One and have recently upgraded the version. Somehow the updated version doesn't work, with the pop up saying "quit unexpectedly". I went to preference in the library folder and had to delete a .plist file in order for this updated version to work. NB. the version I used before was working. I'd like to understand why I had to go through this step for an updated application to work.