Running 7.1.2. TN/transaction monitoring in MWS was working just fine, then suddenly, when trying to query documents, we got the following:

com.webMethods.portlet.tn.utils.TNException: 9999:wm.tn.portal.queries:getQueryResults encountered execution error. Vector Enumeration

at com.webMethods.portlet.tn.utils.TNException.getNewException(TNException.java:52)
at com.webMethods.portlet.tn.utils.TNException.getNewException(TNException.java:40)
at com.webMethods.portlet.wm_tn_ta_searchresults.Wm_tn_ta_searchResultsViewPage.getCurrentPage(Wm_tn_ta_searchResultsViewPage.java:454)
at com.webMethods.portlet.wm_tn_ta_searchresults.Wm_tn_ta_searchResultsViewPage.getColumns(Wm_tn_ta_searchResultsViewPage.java:483)
at com.webMethods.portlet.wm_tn_ta_searchresults.Wm_tn_ta_searchResultsViewPage.beforeRenderResponse(Wm_tn_ta_searchResultsViewPage.java:275)
at com.webMethods.caf.faces.bean.BaseViewBean.beforePhase(BaseViewBean.java:85)
at com.webMethods.caf.faces.bean.FacesBeanPhaseListener.beforePhase(FacesBeanPhaseListener.java:30)
at com.webMethods.caf.faces.portlet.PortletLifecycle.phase(PortletLifecycle.java:241)
at com.webMethods.caf.faces.portlet.PortletLifecycle.render(PortletLifecycle.java:179)
at com.webMethods.caf.faces.portlet.FacesPortlet.render(FacesPortlet.java:417)
at com.webMethods.portal.framework.portletcontainer.impl.PortletApplicationHandler.process(PortletApplicationHandler.java:492)
at com.webMethods.portal.framework.portletcontainer.servlet.PortletServlet.service(PortletServlet.java:58)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:428)
at org.mortbay.jetty.servlet.WebApplicationHandler.dispatch(WebApplicationHandler.java:473)
at org.mortbay.jetty.servlet.Dispatcher.dispatch(Dispatcher.java:286)
at org.mortbay.jetty.servlet.Dispatcher.include(Dispatcher.java:163)
at com.webMethods.portal.framework.portletcontainer.PortletContainer.dispatch(PortletContainer.java:220)
at com.webMethods.portal.framework.portletcontainer.PortletContainer.process(PortletContainer.java:129)
at com.webMethods.portal.framework.portletcontainer.PortletContainer.renderPortlet(PortletContainer.java:102)
at com.webMethods.portal.framework.portletcontainer.beans.PortletBean.processRequest(PortletBean.java:166)
at com.webMethods.portal.framework.portletcontainer.beans.PortletBean.getContentInternal(PortletBean.java:72)
at com.webMethods.portal.framework.portlet.beans.BasicPortletBean.getContent(BasicPortletBean.java:143)
at com.webMethods.portal.mech.portlet.impl.PortletMechanics.getPortletContent(PortletMechanics.java:95)
at com.webMethods.portal.mech.storage.page.PortletHelper.initializeRuntimeProperties(PortletHelper.java:246)
at com.webMethods.portal.mech.storage.page.PortletHelper.initializeRuntimeProperties(PortletHelper.java:302)
at com.webMethods.portal.mech.storage.page.PortletHelper.getFullyInitializedBean(PortletHelper.java:358)
at com.webMethods.portal.mech.portlet.impl.PortletMechanics.resolveWiringProperty(PortletMechanics.java:631)
at com.webMethods.portal.mech.portlet.impl.PortletMechanics.resolveWiring(PortletMechanics.java:610)
at com.webMethods.portal.mech.storage.page.PortletHelper.initializeWiredProperties(PortletHelper.java:224)
at com.webMethods.portal.mech.storage.page.PortletHelper.getInitializedBean(PortletHelper.java:334)
at com.webMethods.portal.mech.storage.page.PortletHelper.getInitializedBean(PortletHelper.java:319)
at com.webMethods.portal.framework.presentation.renderers.FolderRenderer.getRows(FolderRenderer.java:108)
at com.webMethods.portal.framework.presentation.renderers.FolderRenderer.renderContent(FolderRenderer.java:88)
at com.webMethods.portal.framework.presentation.renderers.FolderRenderer.renderPageContent(FolderRenderer.java:68)
at com.webMethods.portal.framework.presentation.renderers.DefaultRenderer.render(DefaultRenderer.java:188)
at com.webMethods.portal.framework.presentation.PresentationManager.handlePres(PresentationManager.java:363)
at com.webMethods.portal.framework.dispatch.DispatchManager.pres(DispatchManager.java:618)
at com.webMethods.portal.framework.dispatch.DispatchManager.handle(DispatchManager.java:458)
at com.webMethods.portal.framework.dispatch.DispatchManager.handleDispatch(DispatchManager.java:371)
at com.webMethods.portal.framework.impl.PortalServlet.service(PortalServlet.java:242)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:428)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:830)
at com.webMethods.portal.framework.impl.NTLMFilter.doFilter(NTLMFilter.java:50)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:821)
at com.webMethods.caf.faces.servlet.GZIPFilter.doFilter(GZIPFilter.java:34)
at org.mortbay.jetty.servlet.WebApplicationHandler$CachedChain.doFilter(WebApplicationHandler.java:821)
at org.mortbay.jetty.servlet.WebApplicationHandler.dispatch(WebApplicationHandler.java:471)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:568)
at org.mortbay.http.HttpContext.handle(HttpContext.java:1530)
at org.mortbay.jetty.servlet.WebApplicationContext.handle(WebApplicationContext.java:633)
at org.mortbay.http.HttpContext.handle(HttpContext.java:1482)
at com.webMethods.portal.webApplication.WmWebAppContext.handle(WmWebAppContext.java:159)
at org.mortbay.http.HttpServer.service(HttpServer.java:909)
at org.mortbay.http.HttpConnection.service(HttpConnection.java:820)
at org.mortbay.http.HttpConnection.handleNext(HttpConnection.java:986)
at org.mortbay.http.HttpConnection.handle(HttpConnection.java:837)
at org.mortbay.http.SocketListener.handleConnection(SocketListener.java:245)
at org.mortbay.util.ThreadedServer.handle(ThreadedServer.java:357)
at org.mortbay.util.ThreadPool$PoolThread.run(ThreadPool.java:534)

We restarted the MWS service and things seem to be back to normal, but this was disconcerting. Any ideas?

Since the error intermittent and gone after restart, I would say check with SAG support with an incident and escalate it:

HTH,
RMG