Re: [rules-users] RuntimeDroolsException: Unable to load

Hi Mark, Thank for the tips. : ) I have added the required mvel14-1.2.8.jar in my classpath. However, I still encounter the same error. Could it be a class loader issue or JRE version? I tried to trace the class loader. Drools is used in my application (running in netbeans). My application is using java.net.FactoryURLClassLoader. On plain netbeans project (before the error occurs), the class loader is sun.misc.Launcher$AppClassLoader. My netbeans is using JRE v 1.6.0 The error occurs when PackageBuilder is initialised. Package Builder builder = new PackageBuilder(); Also, for the Drools Eclipse plugin (on a seperate occassion), when i import some codes, it prompt me that Drools project is not a Java 5.0 project. Best regards! Eric Chong Minsk Goh wrote: MVEL is a required jar, not an optional one, put it on your classpath and hopefully this should work for you.