anonymous wrote : java.lang.ClassNotFoundException: Unexpected error during load of: com.demo.hello.HelloBeanBean, msg=Bad version number in .class file | at You probably compiled it with a higher version of JDK and are using JBoss with a lower version of Java. What do the following commands output? echo %JAVA_HOME% java -version Also ensure that your Eclipse is not pointing to some other JDK version for compiling. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4172824#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...