Specified library jar Week_2_2.jar does not exist: C:\Users\JACK%20WONG\Documents\NetBeansProjects\Week_2_2\dist\Week_2_2.jar
You said the jar does exist; but did you look for "C:\Users\JACK%20WONG\Documents\NetBeansProjects\Week_2_2\dist\Week_2_2.jar" or did you look for "C:\Users\JACK WONG\Documents\NetBeansProjects\Week_2_2\dist\Week_2_2.jar"? You'll notice that some URL-encoding has been done, and perhaps it was done incorrectly. And that URL-encoding, if it's incorrect, is probably not under your control. So you could consider not putting the jar in a path whose name contains a space.