Java Applet Troubleshoot

If the program is not displayed first check the following,

  1. Check that Java Code is enabled in your browser.
  2. Check that you have at least java 1.3 or later installed on your computer.

When I was trying the applet on a Linux system running jvm1.4 I just got a box with a red 'x' in it. Right clicking on it and opening the java console gave:

Java(TM) Plug-in: Version 1.4.2_10 Using JRE version 1.4.2_10 Java HotSpot(TM) Client VM User home directory = /home/martin
Proxy Configuration: Browser Proxy Configuration
c: clear console window
f: finalize objects on finalization queue
g: garbage collect
h: display this help message
l: dump classloader list
m: print memory usage
o: trigger logging
p: reload proxy configuration
q: hide console
r: reload policy configuration
s: dump system properties
t: dump thread list
v: dump thread stack
x: clear classloader cache 0-5: set trace level to <n>
java.lang.UnsupportedClassVersionError: ThreeDTransform/ThreeDImageTransformApplet (Unsupported major.minor version 49.0)
at java.lang.ClassLoader.defineClass0(Native Method)
at java.lang.ClassLoader.defineClass(
at sun.applet.AppletClassLoader.findClass(
at java.lang.ClassLoader.loadClass(
at sun.applet.AppletClassLoader.loadClass(
at java.lang.ClassLoader.loadClass(
at sun.applet.AppletClassLoader.loadCode(
at sun.applet.AppletPanel.createApplet(
at sun.plugin.AppletViewer.createApplet(
at sun.applet.AppletPanel.runLoader(


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