title: DuplicateServiceException JBoss Server
body: <p>I am getting a weird error when trying to run an EAR on my Wildfly 10 Server. It says <code>.session is already registered</code>, which other similar bugs have supposedly been caused by multiple applications using the same <code>context-root</code>. But I am just deploying a single EAR so I'm confused.</p>
  
  <pre class="lang-none prettyprint-override"><code>09:57:30,654 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-8) MSC000001: Failed to start service jboss.deployment.subunit."********.ear"."*********.war".INSTALL: org.jboss.msc.service.StartException in service jboss.deployment.subunit."***********.ear"."**********".INSTALL: WFLYSRV0153: Failed to process phase INSTALL of subdeployment "******.war" of deployment "*******.ear"
      at org.jboss.as.server.deployment.DeploymentUnitPhaseService.start(DeploymentUnitPhaseService.java:154)
      at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1948)
      at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1881)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
      at java.lang.Thread.run(Thread.java:745)
  
  
  Caused by: org.jboss.msc.service.DuplicateServiceException: Service jboss.undertow.deployment.default-server.default-host./******.session is already registered
  </code></pre>