The hot deployer scans the deploy directory every 5 seconds looking for changes. If you are in the middle of deploying an archive file (that is, it is only partially copied), such as an EAR or WAR file, the hot deployer will attempt to open it and run into this error. The best way to deploy is to copy the archive to a temporary location on the same partition as the deploy directory, and then move the archive to the deploy directory. Since you are using Net Beans, and Net Beans uses Ant for its builds, you should be able to modify the build file to do this for deployment. (This is a guess on my part, I have not tried it.) View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4222681#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...