I have a JAR file named helloworld.jar. In order to run it, I\'m executing the following command in a command-line window:
Easiest route is probably upgrading or re-installing the Java Runtime Environment (JRE).
Or this:
C:\Program Files\Java\j2re1.4.2_04\bin\javaw.exe" -jar "%1" %
(Note: the part starting with 'javaw' must be exactly like that; the other part of the path name can vary depending on which version of Java you're using) then press the OK buttons until all the dialogs are closed.Which was stolen from here: http://windowstipoftheday.blogspot.com/2005/10/setting-jar-file-association.html