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Stack trace

java.io.IOException: Failed to persist config.xml\n\tat hudson.model.ItemGroupMixIn.createProjectFromXML(ItemGroupMixIn.java:299)\n\tat hudson.model.ItemGroupMixIn.createTopLevelItem(ItemGroupMixIn.java:194)\n\tat jenkins.model.Jenkins.doCreateItem(Jenkins.java:3102)\n\tat jenkins.model.Jenkins.doCreateItem(Jenkins.java:308)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n\tat java.lang.reflect.Method.invoke(Method.java:606)\n\tat org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:320)\n\tat org.kohsuke.stapler.Function.bindAndInvoke(Function.java:163)\n\tat org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:96)\n\tat org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:124)\n\tat org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:58)\n\tat org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:746)\n\tat org.kohsuke.stapler.Stapler.invoke(Stapler.java:876)\n\tat org.kohsuke.stapler.Stapler.invoke(Stapler.java:649)\n\tat org.kohsuke.stapler.Stapler.service(Stapler.java:238)\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:848)\n\tat org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:686)\n\tat org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1494)\n\tat hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:135)\n\tat hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:126)\n\tat org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1482)\n\tat hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:49)\n\tat org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1482)\n\tat hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:84)\n\tat hudson.security.UnwrapSecurityExceptionFilter.doFilter(UnwrapSecurityExceptionFilter.java:51)\n\tat hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)\n\tat jenkins.security.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:117)\n\tat hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)\n\tat org.acegisecurity.providers.anonymous.AnonymousProcessingFilter.doFilter(AnonymousProcessingFilter.java:125)\n\tat hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)\n\tat org.acegisecurity.ui.rememberme.RememberMeProcessingFilter.doFilter(RememberMeProcessingFilter.java:142)\n\tat hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)\n\tat org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:271)\n\tat hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)\n\tat jenkins.security.BasicHeaderProcessor.success(BasicHeaderProcessor.java:140)\n\tat jenkins.security.BasicHeaderProcessor.doFilter(BasicHeaderProcessor.java:82)\n\tat hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)\n\tat org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:249)\n\tat hudson.security.HttpSessionContextIntegrationFilter2.doFilter(HttpSessionContextIntegrationFilter2.java:67)\n\tat hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)\n\tat hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)\n\tat hudson.security.HudsonFilter.doFilter(HudsonFilter.java:171)\n\tat org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1482)\n\tat org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:49)\n\tat org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1482)\n\tat hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:81)\n\tat org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1482)\n\tat org.kohsuke.stapler.DiagnosticThreadNameFilter.doFilter(DiagnosticThreadNameFilter.java:30)\n\tat org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1474)\n\tat org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:499)\n\tat org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:137)\n\tat org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:533)\n\tat org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:231)\n\tat org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1086)\n\tat org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:428)\n\tat org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:193)\n\tat org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1020)\n\tat org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:135)\n\tat org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:116)\n\tat org.eclipse.jetty.server.Server.handle(Server.java:370)\n\tat org.eclipse.jetty.server.AbstractHttpConnection.handleRequest(AbstractHttpConnection.java:489)\n\tat org.eclipse.jetty.server.AbstractHttpConnection.content(AbstractHttpConnection.java:960)\n\tat org.eclipse.jetty.server.AbstractHttpConnection$RequestHandler.content(AbstractHttpConnection.java:1021)\n\tat org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:865)\n\tat org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:240)\n\tat org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:82)\n\tat org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:668)\n\tat org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:52)\n\tat winstone.BoundedExecutorService$1.run(BoundedExecutorService.java:77)\n\tat java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)\n\tat java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)\n\tat java.lang.Thread.run(Thread.java:745)\nCaused by: javax.xml.transform.TransformerException: org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 1; Content is not allowed in prolog.\n\tat com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:758)\n\tat com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:359)\n\tat jenkins.util.xml.XMLUtils._transform(XMLUtils.java:96)\n\tat jenkins.util.xml.XMLUtils.safeTransform(XMLUtils.java:63)\n\tat hudson.model.ItemGroupMixIn.createProjectFromXML(ItemGroupMixIn.java:279)\n\t... 73 more\nCaused by: org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 1; Content is not allowed in prolog.\n\tat com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1239)\n\tat com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transformIdentity(TransformerImpl.java:677)\n\tat com.sun.org.apache.xalan.internal.xsltc.trax.TransformerImpl.transform(TransformerImpl.java:746)\n\t... 77 more\n