From JBT, deploying an app can seem to be OK (no errors in log, app accessible from browser) but you'll see a foo.war.failed file instead of foo.war.deployed in the deployments folder. The error message talks about duplicate resource.

Very frequently, webapps are being undeployed right after being deployed ------------------------------------------------------------------------ Key: JBIDE-16950 URL: https://issues.jboss.org/browse/JBIDE-16950 Project: Tools (JBoss Tools) Issue Type: Bug Components: server Affects Versions: 4.2.0.Beta1 Environment: Win 7-64, JDK 7, AS 7.1.1, WildFly 8.0.0 Reporter: Fred Bricon Assignee: Rob Stryker Priority: Blocker Labels: respin-b Fix For: 4.2.0.Beta1 I'm experiencing this issue where, after doing a full publishing, the deployed webapp is being undeployed right after being deployed. See http://screencast.com/t/JmwA0TlBrDWX The most reliable way (even though it's not 10% of the time) to reproduce the issue is to deploy a webapp to AS 7.1.1 or WF8, then remove it from the server, deploy it back. That's when the problem occurs : {noformat} 14:13:45,356 INFO [org.jboss.as.server.deployment] (MSC service thread 1-7) JBAS015876: Starting deployment of "dontundeployme.war" (runtime-name: "dontundeployme.war") 14:13:45,485 INFO [org.wildfly.extension.undertow] (MSC service thread 1-4) JBAS017534: Registered web context: /dontundeployme 14:13:45,683 INFO [org.jboss.as.server] (DeploymentScanner-threads - 1) JBAS018559: Deployed "dontundeployme.war" (runtime-name : "dontundeployme.war") 14:13:50,708 INFO [org.wildfly.extension.undertow] (MSC service thread 1-6) JBAS017535: Unregistered web context: /dontundeployme 14:13:50,730 INFO [org.jboss.as.server.deployment] (MSC service thread 1-5) JBAS015877: Stopped deployment dontundeployme.war (runtime-name: dontundeployme.war) in 23ms 14:13:50,999 INFO [org.jboss.as.server] (DeploymentScanner-threads - 1) JBAS018558: Undeployed "dontundeployme.war" (runtime-name: "dontundeployme.war") 14:13:56,004 INFO [org.jboss.as.server.deployment.scanner] (DeploymentScanner-threads - 2) JBAS015003: Found dontundeployme.war in deployment directory. To trigger deployment create a file called dontundeployme.war.dodeploy {noformat} Also, pretty quite frequently, deployment just fails (but I haven't been able to figure out a decisive pattern yet) as the server thinks deployments are duplicates (see screencast)