If your plug-in runs flawlessly in your development environment (e.g., Eclipse PDE) but not in your production environment, you might suffer from a ClassDefNotFoundError.

The Problem:

First of all, you may consult the Eclipse Error Log in your production environment to confirm that there is actually a ClassDefNotFoundError thrown. Then, have a look into the JAR created by the Export Wizard: you won’t find the classes expected by your plug-in because the Export Wizard seems to miss some class files.

The Solution:

If you found that the Export Wizard is not exporting all class files but your plug-in works well in you development environment select the option Use class files compiled in the workspace (Options tab) in the Export Wizard.

Good luck!