Question

Any fix to avoid this exception while starting WLDF Console? Thanks.

java.lang.ClassFormatError: Incompatible magic value 218762506 in class file com/bea/diagnostics/dashboard/ChartPanelApplet
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClassCond(Unknown Source)
    at java.lang.ClassLoader.defineClass(Unknown Source)
    at java.security.SecureClassLoader.defineClass(Unknown Source)
    at sun.plugin2.applet.Applet2ClassLoader.findClass(Unknown Source)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Unknown Source)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.plugin2.applet.Plugin2ClassLoader.loadCode(Unknown Source)
    at sun.plugin2.applet.Plugin2Manager.createApplet(Unknown Source)
    at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Exception: java.lang.ClassFormatError: Incompatible magic value 218762506 in class file com/bea/diagnostics/dashboard/ChartPanelApplet

Answer 1

There is an earlier Sun bug report on this issue, with JDK 1.4

you are mostly running JDK 1.6 but take a look at the bug report.

Short Summary (gleaned from this forum) :

The Java plug-in of your browser tries
to get some .class file from the
current location (your server) and
fails because your server returns some
custom 404 page. Let’s try to check
the Java console to see what really is
requested. Please, run the Java
console, set the trace level to 5
(highest level).

Enable the Java console on Windows for IE browser and see if it gives a detail on which URL is giving the 404 or some other error.

Further Reading

Oracle forum question