Hi,

I'm using courselab 2.4 and I want to add jar file(applet java) to a slide.
But there is a problem when I make a preview ( error message: ClassNotFound Exception)

Please I need your help

Thank you

So lets make tw cases, one of these is the problem and key to the solution:

#1 Making the assumption that you have the class package in your java folder, the JVM has traversed you folder(s) of classes looking for this one and it can't find it.
In this case the path to the class is either missing, incorrect or otherwise wrong.
Re-install the class and check the path JVM is using is correct.

#2 You are making the assumption that the class package is a part of the normal java install and this class is therefore in your java folder, the JVM has traversed you folder(s) of classes looking for this one and it can't find it. The class is NOT a standard class.
In this case the class doesn't exist.

Java is really bad at this kind of thing, the paths often go wrong and the error reporting can be confusing.
Classes can be things java is bundled with as standard, can be other official java class libraries or collections or third party class files.
If you don't understand the above then you need to do some serious reading of you want to use java and JARS in this way

An after thought... If you do add or pack in any java classes or collections then check the T&C's official java stuff shouldn't be reengineered or redistributed.