tmmaluleke [https://community.jboss.org/people/tmmaluleke] created the discussion "cannot be cast to org.jbpm.task.service.TaskClientHandler$TaskOperationResponseHandler" To view the discussion, visit: https://community.jboss.org/message/779055#779055 -------------------------------------------------------------- Hello, What my be the cause of this error: I'm using  jbpm5.3 with eclipse | 0 | 29/11 09:16:00,648[Thread-2] ERROR service.hornetq.HornetQTaskClientConnector.run  - org.jbpm.task.service.responsehandlers.BlockingTaskSummaryResponseHandler cannot be cast to org.jbpm.task.service.TaskClientHandler$TaskOperationResponseHandler | Exception in thread "Thread-2" java.lang.RuntimeException: Client Exception with class class org.jbpm.task.service.hornetq.HornetQTaskClientConnector$1 using port 5445 | | at org.jbpm.task.service.hornetq.HornetQTaskClientConnector$1.run(HornetQTaskClientConnector.java:134) | | | at java.lang.Thread.run(Unknown Source) | Caused by: java.lang.ClassCastException: org.jbpm.task.service.responsehandlers.BlockingTaskSummaryResponseHandler cannot be cast to org.jbpm.task.service.TaskClientHandler$TaskOperationResponseHandler | | at org.jbpm.task.service.TaskClientHandler.messageReceived(TaskClientHandler.java:64) | | | at org.jbpm.task.service.hornetq.HornetQTaskClientHandler.messageReceived(HornetQTaskClientHandler.java:56) | | | at org.jbpm.task.service.hornetq.HornetQTaskClientConnector$1.run(HornetQTaskClientConnector.java:120) | | | ... 1 more | -------------------------------------------------------------- Reply to this message by going to Community [https://community.jboss.org/message/779055#779055] Start a new discussion in jBPM at Community [https://community.jboss.org/choose-container!input.jspa?contentType=1&...]