Java exception for some computers stop SCORM 1.2 courses from playing

I found one thread with this discussion, but no answer. We have a single course that does not play on some computers. It's published to SCORM 1.2 and plays in SAP LSO. The error we get in the java console says:

"basic: error: Incompatible magic value 1008813135 in class file TitleMgrApplet.

java.lang.ClassFormatError: Incompatible magic value 1008813135 in class file TitleMgrApplet

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 1008813135 in class file TitleMgrApplet

Ignored exception: java.lang.ClassFormatError: Incompatible magic value 1008813135 in class file TitleMgrApplet

Other than trying to publish the course again, not really sure where to begin looking, as this only happens occasionally. We tried different browsers and uninstalled java, then reinstalled. Reinstalling works on some machines, but not all.

Thanks,

Scott