[rules-users] How do I prevent the package registry from being null in my package builder?

I just installed Drools and wanted to build a simple RuleFlow. But When I add any process containing constraints or rules to my Knowledgebuilder, I'm always getting a NullPointerException, because the "package registry" seems to be null. ..... java.lang.NullPointerException at org.drools.compiler.ProcessBuilder.buildProcess(ProcessBuilder.java:119) at org.drools.compiler.ProcessBuilder.addProcessFromFile(ProcessBuilder.java:223) at org.drools.compiler.PackageBuilder.addProcessFromXml(PackageBuilder.java:447) at org.drools.compiler.PackageBuilder.addKnowledgeResource(PackageBuilder.java:503) at org.drools.builder.impl.KnowledgeBuilderImpl.add(KnowledgeBuilderImpl.java:25) ..... ProcessBuilder.java:118 PackageRegistry pkgRegistry = this.packageBuilder.getPackageRegistry(process.getPackageName()); ProcessBuilder.java:119 org.drools.rule.Package p = pkgRegistry.getPackage(); ..... The ruleflow is successfully validated though when i press that button in eclipse... Can somebody give me a hint what's missing? Thanks! -- View this message in context: http://drools-java-rules-engine.46999.n3.nabble.com/How-do-I-prevent-the-... Sent from the Drools - User mailing list archive at Nabble.com.