# DefaultExceptionMapper Errors **URL:** \ **Category:** Ignition\ **Created:** [May 7, 2018, 2:36pm UTC](https://forum.inductiveautomation.com/t/defaultexceptionmapper-errors/17944 "2018-05-07T14:36:24Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![WillMT10](https://avatars.discourse-cdn.com/v4/letter/w/7feea3/32.png) [@WillMT10](https://forum.inductiveautomation.com/u/WillMT10)\ **Post date:** [May 7, 2018, 2:36pm UTC](https://forum.inductiveautomation.com/t/defaultexceptionmapper-errors/17944/1 "2018-05-07T14:36:24Z")
I’ve been seeing an odd error pop up in the Logs for a couple of our gateways (one is Ignition 7.9.6 and the other is 7.9.7). When the error triggers, there will often be 10 separate error events that appear in the log, all with the same timestamp. If you expand the error to read the entire error, it will expand all 10 separate error events in the log at the same time (hopefully that makes sense). I just want to make sure there is nothing I need to be worried about with this error and if there is anything I can do to stop it. Any help would be appreciated! Both gateways are PC’s with one running Windows Server 2012 the other running Windows 7. Both are running Java 8. Here is the error: ```auto DefaultExceptionMapper unexpected exception when handling another exception: Header was already written to response! java.lang.IllegalStateException: Header was already written to response! at org.apache.wicket.protocol.http.HeaderBufferingWebResponse.checkHeader(HeaderBufferingWebResponse.java:64) at org.apache.wicket.protocol.http.HeaderBufferingWebResponse.sendError(HeaderBufferingWebResponse.java:105) at org.apache.wicket.request.http.handler.ErrorCodeRequestHandler.respond(ErrorCodeRequestHandler.java:77) at org.apache.wicket.request.cycle.RequestCycle$HandlerExecutor.respond(RequestCycle.java:814) at org.apache.wicket.request.RequestHandlerStack.execute(RequestHandlerStack.java:64) at org.apache.wicket.request.cycle.RequestCycle.executeExceptionRequestHandler(RequestCycle.java:302) at org.apache.wicket.request.cycle.RequestCycle.executeExceptionRequestHandler(RequestCycle.java:311) at org.apache.wicket.request.cycle.RequestCycle.executeExceptionRequestHandler(RequestCycle.java:311) at org.apache.wicket.request.cycle.RequestCycle.executeExceptionRequestHandler(RequestCycle.java:311) at org.apache.wicket.request.cycle.RequestCycle.executeExceptionRequestHandler(RequestCycle.java:311) at org.apache.wicket.request.cycle.RequestCycle.executeExceptionRequestHandler(RequestCycle.java:311) at org.apache.wicket.request.cycle.RequestCycle.executeExceptionRequestHandler(RequestCycle.java:311) at org.apache.wicket.request.cycle.RequestCycle.executeExceptionRequestHandler(RequestCycle.java:311) at org.apache.wicket.request.cycle.RequestCycle.executeExceptionRequestHandler(RequestCycle.java:311) at org.apache.wicket.request.cycle.RequestCycle.executeExceptionRequestHandler(RequestCycle.java:311) at org.apache.wicket.request.cycle.RequestCycle.processRequest(RequestCycle.java:225) at org.apache.wicket.request.cycle.RequestCycle.processRequestAndDetach(RequestCycle.java:281) at org.apache.wicket.protocol.http.WicketFilter.processRequest(WicketFilter.java:188) at org.apache.wicket.protocol.http.WicketFilter.doFilter(WicketFilter.java:245) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1668) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:581) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143) at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:548) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:226) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1160) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:511) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1092) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) at org.eclipse.jetty.server.handler.HandlerList.handle(HandlerList.java:52) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:134) at org.eclipse.jetty.server.Server.handle(Server.java:518) at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:308) at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:244) at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:273) at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:95) at org.eclipse.jetty.io.SelectChannelEndPoint$2.run(SelectChannelEndPoint.java:93) at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.produceAndRun(ExecuteProduceConsume.java:246) at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.run(ExecuteProduceConsume.java:156) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:654) at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:572) ``` ---
**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\ **Post date:** [May 7, 2018, 2:42pm UTC](https://forum.inductiveautomation.com/t/defaultexceptionmapper-errors/17944/2 "2018-05-07T14:42:27Z")
Yeah, I’ve seen this, too. Very annoying. ---
**Author:** ![StefanGronberg](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/stefangronberg/32/6288_2.png) [@StefanGronberg](https://forum.inductiveautomation.com/u/StefanGronberg)\ **Post date:** [September 20, 2018, 11:02am UTC](https://forum.inductiveautomation.com/t/defaultexceptionmapper-errors/17944/3 "2018-09-20T11:02:15Z")
I have noticed with my current project this error is spit out several times, Just last time 7 minutes ago there is 20 or so lines with this error. I am not sure if it occurs the same time the trial expires after 2 hours, but time stamp seems to be around the same time. ---
**Author:** ![byrnep](https://avatars.discourse-cdn.com/v4/letter/b/db5fbb/32.png) [@byrnep](https://forum.inductiveautomation.com/u/byrnep)\ **Post date:** [July 9, 2019, 4:41pm UTC](https://forum.inductiveautomation.com/t/defaultexceptionmapper-errors/17944/4 "2019-07-09T16:41:37Z")
Replying to promote. We’ve seen this issue ourselves and the log message is not detailed enough to explain what the cause is. Is there any thing that can be done? Version 7.9.10 ---
**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\ **Post date:** [July 9, 2019, 5:03pm UTC](https://forum.inductiveautomation.com/t/defaultexceptionmapper-errors/17944/5 "2019-07-09T17:03:18Z")
This is the same issue as this other thread. It's on our radar, but at a low priority, because it doesn't actually cause any problems. > [@Errors in logs with unknown origin](http://forum.inductiveautomation.com/t/errors-in-logs-with-unknown-origin/21712): > > I try to keep the logs of our installations clean, as this makes it easier to find problems. But here’s an error we get on regular basis of which we can’t find the origin. It’s probably related to something we did, as it happends on a certain project, no matter where we install the backup. But I have no idea where to look for the origin of this issue. INFO | jvm 1 | 2019/01/07 15:41:59 | E [o.a.w.DefaultExceptionMapper] [15:41:59]: unexpected exception when handling another exception: … ---
**Author:** ![paul-griffith](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/paul-griffith/32/37249_2.png) [@paul-griffith](https://forum.inductiveautomation.com/u/paul-griffith)\ **Post date:** [July 9, 2019, 5:03pm UTC](https://forum.inductiveautomation.com/t/defaultexceptionmapper-errors/17944/6 "2019-07-09T17:03:22Z")