Hello, I am using jBPM 5.4 with persistence and have long running processes and make make changes to the knowledge base periodically (via drools guvnor 5.5). I use JPAKnowlegeService.loadStatefulKnowledgeSession(...) to retrieve my existing knowledge session. When I make a change to the rule base (via drools 5.5 guvnor) and then try to restart my application (and reload the knowledgesession) I get an exception: java.lang.RuntimeException: Unable to load session snapshot at org.drools.persistence.SessionMarshallingHelper.loadSnapshot(SessionMarshallingHelper.java:96) . . Caused by: java.lang.NullPointerException at org.drools.common.Scheduler$activationTimerInputMarshaller.deserialize(Scheduler.java:230) I am NOT currently using a KnowledgeAgent and it seems like it should be able to help. I have read over the drools forum and this one and see a few discussions on the topic (https://community.jboss.org/thread/172818) but nothing concrete to put me on the right path. The examples with knowledgeagent I have found assume that I am calling: StatefulKnowledgeSession ksession = kbase.newStatefulKnowledgeSession(); Can someone please show/explain how I can reload an existing persisted knowledgesession given changes in my knowledge base? (for example, can the knowledgeagent and JPAKnowlegeService.loadStatefulKnowledgeSession be used together? If not, do I load the existing statefulknowledgesession by some other means?) I am using Spring-based configuration. Thanks for any insight. -J -- View this message in context: http://drools.46999.n3.nabble.com/Using-KnowledgeAgent-with-loadStatefulK... Sent from the Drools: User forum mailing list archive at Nabble.com.