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layout: default_md title: Errors title-class: page-title-activemq5 type: activemq5

 FAQ > Errors

Questions on specific kinds of errors. If you have seen a specific exception then check the Exceptions

• Could not find PacketReader for packet type - UNKNOWN PACKET TYPE
• Exceptions
  • certificate_unknown
  • IOException - could not find class for resource
  • java.io.InterruptedIOException
  • java.io.IOException Failed to create database ‘derbydb’, see the next exception for details
  • java.lang.NoSuchMethodError
  • java.lang.NoSuchMethodException org.activemq.ra.ActiveMQResourceAdapter.setUseEmbeddedBroker
  • java.lang.OutOfMemory
  • javax.jms.JMSException - Wire format negociation timeout - peer did not send his wire format.
  • JAXB 2.0 API is being loaded from the bootstrap classloader, but this RI () needs 2.1 API.
  • JAXB 2.0 API is being loaded from the bootstrap classloader, but this RI (xxx) needs 2.1 API
  • Journal is already opened by this application
  • NoClassDefFoundError - org.springframework.core.io.Resource
  • No suitable driver
• I am having problems with the Spring JmsTemplate
• I am not receiving any messages, what is wrong
• I cannot connect to ActiveMQ from JConsole
• I do not receive messages in my second consumer
• I get errors building the code whats wrong
• log4j-WARN No appenders could be found for logger
• Multicast - Watch out for IPV6 vs IPV4 support on your operating system or distribution or network
• My producer blocks
• onMessage method of MessageListener is never called
• Resource Adapter does not seem to pool connections
• Slow networks drop large messages
• The Broker will not start
• The vm transport starts a broker before my configured broker starts
• Why do I not get all of the messages I sent
• Why do I not receive messages on my durable topic subscription
• Why do KahaDB log files remain after cleanup