Currently working on deployeing a web application(with Grails) on wildlfy 17. The WAR gets deployed but when i run a specific action at runtime, I am getting the following error(stacktrace minified): WARN [org.jboss.modules.define] (default task-18) Failed to define class org.jboss.ws.core.jaxws.spi.ProviderImpl in Module "com.project" from local module loader @68b6f0d6 (finder: local module finder @4044fb95 (roots: C:\Programs\Wildfly\modules,C:\Programs\Wildfly\modules\system\layers\base)): java.lang.NoClassDefFoundError: Failed to link org/jboss/ws/core/jaxws/spi/ProviderImpl (Module "com.project" from local module loader @68b6f0d6 (finder: local module finder @4044fb95 (roots: C:\IDeaS\CMA\G302\Programs\Wildfly\modules,C:\Programs\Wildfly\modules\system\layers\base))): javax/xml/ws/spi/Provider ERROR [StackTrace] (default task-18) Full Stack Trace:: javax.xml.ws.WebServiceException: Error while searching for service [javax.xml.ws.spi.Provider] Caused by: java.lang.NoClassDefFoundError: Failed to link org/jboss/ws/core/jaxws/spi/ProviderImpl (Module "com.project" from local module loader @68b6f0d6 (finder: local module finder @4044fb95 (roots: C:\Programs\Wildfly\modules,C:\\Programs\Wildfly\modules\system\layers\base))): javax/xml/ws/spi/Provider ERROR [StackTrace] (default task-18) Full Stack Trace:: java.lang.NoClassDefFoundError: Failed to link org/jboss/ws/core/jaxws/spi/ProviderImpl (Module "com.project" from local module loader @68b6f0d6 (finder: local module finder @4044fb95 (roots: C:\Programs\Wildfly\modules,C:\Programs\Wildfly\modules\system\layers\base))): javax/xml/ws/spi/Provider ERROR [StackTrace] (default task-18) Full Stack Trace:: javax.xml.ws.WebServiceException: Error while searching for service [javax.xml.ws.spi.Provider] Caused by: java.lang.NoClassDefFoundError: Failed to link org/jboss/ws/core/jaxws/spi/ProviderImpl (Module "com.project" from local module loader @68b6f0d6 (finder: local module finder @4044fb95 (roots: C:\Programs\Wildfly\modules,C:\Programs\Wildfly\modules\system\layers\base))): javax/xml/ws/spi/Provider ERROR [org.grails.web.errors.GrailsExceptionResolver] (default task-18) NoClassDefFoundError occurred when processing request: [POST] /cma/Sql/runQuery Failed to link org/jboss/ws/core/jaxws/spi/ProviderImpl (Module "com.project" from local module loader @68b6f0d6 (finder: local module finder @4044fb95 (roots: C:\Programs\Wildfly\modules,C:\Programs\Wildfly\modules\system\layers\base))): javax/xml/ws/spi/Provider. Stacktrace follows:: javax.xml.ws.WebServiceException: Error while searching for service [javax.xml.ws.spi.Provider] Caused by: java.lang.NoClassDefFoundError: Failed to link org/jboss/ws/core/jaxws/spi/ProviderImpl (Module "com.project" from local module loader @68b6f0d6 (finder: local module finder @4044fb95 (roots: C:\Programs\Wildfly\modules,C:\Programs\Wildfly\modules\system\layers\base))): javax/xml/ws/spi/Provider I have added Jars to my projects which contain this classes, I have checked and these classes exists in the WAR file that is produced. Also, these are not there in Wildlfy's modules folder I have created jboss-deployment-structure.xml: <?xml version='1.0' encoding='UTF-8'?> <jboss-deployment-structure xmlns="urn:jboss:deployment-structure:1.2"> <deployment> <exclusions> <module name="org.quartz" /> <module name="org.jboss.ws.core" /> </exclusions> <resources> <resource-root path="jbossws-client.jar" /> </resources> <dependencies> <module name="org.jboss.ws.core" /> </dependencies> </deployment> </jboss-deployment-structure> Here I have tried exclusion, resources and dependencies each one separately but just combined here for simplicity. But none of them seems to work for me. Adding <module name="org.quartz" /> solved my quartz-scheduling problem but does not seem to work for this one. Continue reading...