A couple of thoughts. 1) Try downloading it again, and verify the download with md5. I have successfully downloaded it to various machines, and run it without encountering this issue. (Thinking about this some more, if the download was bad, Windows would probably complain about a zipfile error, so this has a low probability of success.) 2) Try it on another PC. If it works there, you need to figure out what is the difference between your PC and that PC. That gives me an idea. Do you have listdlls? If not download it from http://www.microsoft.com/technet/sysinternals/utilities/listdlls.mspx, then run the app server, and then at another command prompt enter: listdlls java Post the output, perhaps there is a stray DLL causing the problem. Oh, by the way, do you have any JAR files in the JVMs endorsed directory? If you are not sure, install another version of the JDK, set JAVA_HOME to it, and try again. If that works, then an endorsed JAR is messing you up. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4084043#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...