For test purpose, We need to create EBS on Oracle VM box.  After installation some of our user cant login to our new test system. To can see what happen, We just enabled java to debug console on client machines.

While We checked the end of the console We noticed those errors:

at sun.applet.AppletClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.applet.AppletClassLoader.loadCode(Unknown Source)
at sun.applet.AppletPanel.createApplet(Unknown Source)
at sun.plugin.AppletViewer.createApplet(Unknown Source)
at sun.applet.AppletPanel.runLoader(Unknown Source)
at Source)
at Source)

java.lang.ClassNotFoundException: oracle.apps.fnd.formsClient.FormsLauncher.class

There are some reasons for this message, but possible cause of this error is:

1.If you installed some new features, you can hit this message.

2.Be sure you have certified OS, also browser version.If you have proxy check proxy settings.

3. Check your add-ons from the browser, also check your machine’s  firewall&virus program (Try to disable them)

4. Try to clear browswer and java cash.If its not work than, try to uninstall java and try to install it again


Recommended Browsers for Oracle E-Business Suite Release 12 [ID 389422.1]
Recommended Browsers for Oracle E-Business Suite 11i [ID 285218.1]
Jinitiator Diagnostic script[ID 183549.1]