Thanks for your answer. But I can not upload some large size attachments. When I uploaded some small size attachments. It works perfectly. If I uploaded some attachments which file size greater than 3 MB, It popped an error message like this:
java.lang.NullPointerException at net.jforum.JForumExecutionContext.enableRollback(JForumExecutionContext.java:272) at net.jforum.JForum.service(JForum.java:209) at javax.servlet.http.HttpServlet.service(HttpServlet.java:856) at com.evermind[Oracle Containers for
J2EE 10g (10.1.3.0.0) ].server.http.ResourceFilterChain.doFilter(ResourceFilterChain.java:64) at net.jforum.util.legacy.clickstream.ClickstreamFilter.doFilter(ClickstreamFilter.java:59) at com.evermind[Oracle Containers for J2EE 10g (10.1.3.0.0) ].server.http.ServletRequestDispatcher.invoke(ServletRequestDispatcher.java:629) at com.evermind[Oracle Containers for J2EE 10g (10.1.3.0.0) ].server.http.ServletRequestDispatcher.forwardInternal(ServletRequestDispatcher.java:376) at com.evermind[Oracle Containers for J2EE 10g (10.1.3.0.0) ].server.http.HttpRequestHandler.doProcessRequest(HttpRequestHandler.java:870) at com.evermind[Oracle Containers for J2EE 10g (10.1.3.0.0) ].server.http.HttpRequestHandler.processRequest(HttpRequestHandler.java:451) at com.evermind[Oracle Containers for J2EE 10g (10.1.3.0.0) ].server.http.HttpRequestHandler.serveOneRequest(HttpRequestHandler.java:218) at com.evermind[Oracle Containers for J2EE 10g (10.1.3.0.0) ].server.http.HttpRequestHandler.run(HttpRequestHandler.java:119) at com.evermind[Oracle Containers for J2EE 10g (10.1.3.0.0) ].server.http.HttpRequestHandler.run(HttpRequestHandler.java:112) at oracle.oc4j.network.ServerSocketReadHandler$SafeRunnable.run(ServerSocketReadHandler.java:260) at oracle.oc4j.network.ServerSocketAcceptHandler.procClientSocket(ServerSocketAcceptHandler.java:230) at oracle.oc4j.network.ServerSocketAcceptHandler.access$800(ServerSocketAcceptHandler.java:33) at oracle.oc4j.network.ServerSocketAcceptHandler$AcceptHandlerHorse.run(ServerSocketAcceptHandler.java:831) at com.evermind[Oracle Containers for J2EE 10g (10.1.3.0.0) ].util.ReleasableResourcePooledExecutor$MyWorker.run(ReleasableResourcePooledExecutor.java:303) at java.lang.Thread.run(Thread.java:534)
[originally posted on jforum.net by unsee]