I know this is a repeat. The archives and FAQ offer explanations, but not much help with eliminating this intermittent error. I'm using Tomcat 3.2.1 on WinXP Pro RC2 with MS IE6. Should I move on to Tomcat 3.2.3 or 4.0? Will that help? As noted previously, stopping and restarting tomcat makes the problem go away for awhile, until I make some change to a servlet. Although I have no way of knowing for sure, I hope it's not WinXP. So far, the beta and RC1 haven't been a problem. -- Terry Westley [EMAIL PROTECTED] ------------------------------------------------------------------------------ Error: 500 Location: /sigada2001/index.html Internal Servlet Error: java.lang.IllegalStateException: Can't happen - classname is null, who added this ? at org.apache.tomcat.core.ServletWrapper.loadServlet(ServletWrapper.java:261) at org.apache.tomcat.core.ServletWrapper.init(ServletWrapper.java:289) at org.apache.tomcat.core.Handler.service(Handler.java:254) at org.apache.tomcat.core.ServletWrapper.service(ServletWrapper.java:372) at org.apache.tomcat.core.ContextManager.internalService(ContextManager.java:797) at org.apache.tomcat.core.ContextManager.service(ContextManager.java:743) at org.apache.tomcat.service.http.HttpConnectionHandler.processConnection(HttpConnectionHandler.java:210) at org.apache.tomcat.service.TcpWorkerThread.runIt(PoolTcpEndpoint.java:416) at org.apache.tomcat.util.ThreadPool$ControlRunnable.run(ThreadPool.java:498) at java.lang.Thread.run(Thread.java:484)