title: What does "The prefix "vm" for element "vm:endpoint" is not bound." means and how to solve it?
body: <p>I am trying to integrate mule with drools, I have mainly followed the tutorial <a href="http://www.mulesoft.org/documentation-3.2/display/32X/Drools+Module+Reference" rel="nofollow noreferrer">here</a> but I am getting this error :</p>
  <blockquote>
  <p>&quot;The prefix &quot;vm&quot; for element &quot;vm:endpoint&quot; is not bound.&quot;</p>
  </blockquote>
  <p>can anyone help me solve this problem?</p>
  <p>following is my .drl file and mule flow files.</p>
  <pre><code>&lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&gt;
  &lt;mule 
  xmlns:bpm=&quot;http://www.mulesoft.org/schema/mule/bpm&quot;
  xmlns:http=&quot;http://www.mulesoft.org/schema/mule/http&quot;
  xmlns:tracking=&quot;http://www.mulesoft.org/schema/mule/ee/tracking&quot; xmlns=&quot;http://www.mulesoft.org/schema/mule/core&quot;
  xmlns:doc=&quot;http://www.mulesoft.org/schema/mule/documentation&quot;
  xmlns:spring=&quot;http://www.springframework.org/schema/beans&quot; version=&quot;EE-3.6.0&quot;
  xmlns:xsi=&quot;http://www.w3.org/2001/XMLSchema-instance&quot;
  xsi:schemaLocation=
  &quot;http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-current.xsd
  http://www.mulesoft.org/schema/mule/core http://www.mulesoft.org/schema/mule/core/current/mule.xsd
  http://www.mulesoft.org/schema/mule/http http://www.mulesoft.org/schema/mule/http/current/mule-http.xsd
  http://www.mulesoft.org/schema/mule/ee/tracking http://www.mulesoft.org/schema/mule/ee/tracking/current/mule-tracking-ee.xsd
  http://www.mulesoft.org/schema/mule/bpm http://www.mulesoft.org/schema/mule/bpm/3.6/mule-bpm.xsd&quot;&gt;
      &lt;http:listener-config name=&quot;HTTP_Listener_Configuration&quot;
      host=&quot;localhost&quot; port=&quot;8084&quot; doc:name=&quot;HTTP Listener Configuration&quot; /&gt;
  
      &lt;spring:beans&gt;
          &lt;spring:bean id=&quot;dto&quot; class=&quot;com.hamgam.hit.esb.XMLDTO&quot; scope=&quot;singleton&quot; /&gt;
          &lt;spring:bean id=&quot;dto-convertor&quot; class=&quot;com.hamgam.hit.esb.XMLToDTO&quot; scope=&quot;singleton&quot; /&gt;
          &lt;spring:bean id=&quot;rule-convertor&quot; class=&quot;com.hamgam.hit.esb.RuleXMLToDRL&quot; scope=&quot;singleton&quot; /&gt;           
      &lt;/spring:beans&gt;
  
      &lt;bpm:drools /&gt;
  
      &lt;flow name=&quot;basic_tutorialFlow&quot;&gt;
          &lt;http:listener config-ref=&quot;HTTP_Listener_Configuration&quot; path=&quot;/{name}&quot; doc:name=&quot;HTTP&quot; /&gt;
          &lt;vm:endpoint name = &quot;emc&quot; path=&quot;drool.msg&quot; /&gt;
          &lt;set-variable  variableName=&quot;name&quot; value=&quot;#[message.inboundProperties['http.uri.params']['name']]&quot; /&gt;       
          &lt;set-variable variableName=&quot;msg&quot; value=&quot;#[payload]&quot;/&gt;
          &lt;logger level=&quot;DEBUG&quot; doc:name=&quot;Logger&quot; message=&quot;Current path is flowVars['name']&quot; /&gt;
  
          &lt;expression-component&gt;
          app.registry['dto'] = app.registry['dto-convertor'].convert(flowVars['name']);
          &lt;/expression-component&gt; 
  
          &lt;bpm:rules rulesDefinition=&quot;rule.drl&quot; cepMode=&quot;true&quot; initialFacts-ref=&quot;dto&quot; entryPoint=&quot;XMLDTO stream&quot; /&gt;
      
          &lt;choice doc:name=&quot;Choice&quot;&gt;
              &lt;when expression=&quot;#[flowVars.emc == 'KeyValueMatched']&quot;&gt;
              &lt;set-payload doc:name=&quot;Set Payload&quot; value=&quot;#['KeyValueMatched! You are with us on 8084. ' + flowVars['name'] + '. Today is ' + server.dateTime.format('dd/MM/yy') + '.' ]&quot; /&gt;
              &lt;/when&gt;
              &lt;otherwise&gt;
              &lt;set-payload doc:name=&quot;Set Payload&quot; value=&quot;#['Nothing! You are with us on 8084. ' + flowVars['name'] + '. Today is ' + server.dateTime.format('dd/MM/yy') + '.' ]&quot; /&gt;
              &lt;/otherwise&gt;
          &lt;/choice&gt;
  
      &lt;/flow&gt;
  &lt;/mule&gt;
  </code></pre>
  <p>and the drl file :</p>
  <pre><code>global org.mule.module.bpm.MessageService mule;    
  import com.me.mit.esb.*;
   
  rule &quot;La Vita Ebela&quot;    
  dialect &quot;mvel&quot;
  
  when
      $x:XMLDTO( inputXML == &quot;inputXML&quot; )
  then
      mule.generateMessage(&quot;emc&quot;,  &quot;KeyValueMatched&quot;, null, MessageExchangePattern.ONE_WAY);
  end
  </code></pre>