Steve, I couldn't fathom a guess as to what's going on without actually seeing the jar file. "A Java Exception has occurred" is not something a Java VM would say. This sounds like some kind of pop-up dialog box made by OS X or Windows or whatnot. What happens when you say java -cp myJarFile.jar ? Sean On Apr 1, 2013, at 6:58 PM, Steve Kraska wrote: > Hey Sean, > > Thanks for all of the help. You answer was very thorough and informative. I tried > running those four steps that you have listed but when I tried to run the newly > updated jar file, it simply tells me that "A Java Exception has occurred." > > This does not happen with the jar file that exists initially in the mason folder, so I > was wondering if there was something missing in the fourth step you listed. Do I > need to include the external libraries you mentioned that were not added in order > to get around this exception? Is it a potential problem with using Mason version > 16? I can't quite figure out what is wrong. > > Thank you again, > Steve