OK to beat the sheep on this one. I was attempting to change group names from Upper Case to lower case in JIRA, which seems to have potentially duplicated groups and has now broken Crowd. The groups are showing up in different ways in JIRA, and everytime I try to log into Crowd, I get this error:

System Error System Error

A system error has occured please contact your administrator.
If this problem continues to occur please contact Atlassian by opening a support request with the following information:

• A description of your problem and what you were doing at the time it occurred
• Cut & paste the error and system information found below
• Attach the application server log file (if possible).

Cause :
org.codehaus.xfire.XFireRuntimeException: Could not invoke service.. Nested exception is org.codehaus.xfire.fault.XFireFault: Index: 0, Size: 0

Stack Trace :

org.codehaus.xfire.XFireRuntimeException: Could not invoke service.. Nested exception is org.codehaus.xfire.fault.XFireFault: Index: 0, Size: 0
org.codehaus.xfire.fault.XFireFault: Index: 0, Size: 0
at org.codehaus.xfire.fault.Soap11FaultSerializer.readMessage(Soap11FaultSerializer.java:31)
at org.codehaus.xfire.fault.SoapFaultSerializer.readMessage(SoapFaultSerializer.java:28)
at org.codehaus.xfire.soap.handler.ReadHeadersHandler.checkForFault(ReadHeadersHandler.java:111)
at org.codehaus.xfire.soap.handler.ReadHeadersHandler.invoke(ReadHeadersHandler.java:67)
at org.codehaus.xfire.handler.HandlerPipeline.invoke(HandlerPipeline.java:131)
at org.codehaus.xfire.client.Client.onReceive(Client.java:406)
at org.codehaus.xfire.transport.http.HttpChannel.sendViaClient(HttpChannel.java:139)
at org.codehaus.xfire.transport.http.HttpChannel.send(HttpChannel.java:48)
at org.codehaus.xfire.handler.OutMessageSender.invoke(OutMessageSender.java:26)
at org.codehaus.xfire.handler.HandlerPipeline.invoke(HandlerPipeline.java:131)
at org.codehaus.xfire.client.Invocation.invoke(Invocation.java:79)
at org.codehaus.xfire.client.Invocation.invoke(Invocation.java:114)
at org.codehaus.xfire.client.Client.invoke(Client.java:336)
at org.codehaus.xfire.client.XFireProxy.handleRequest(XFireProxy.java:77)
at org.codehaus.xfire.client.XFireProxy.invoke(XFireProxy.java:57)
at $Proxy15.authenticatePrincipal(Unknown Source)
at com.atlassian.crowd.integration.service.soap.client.SecurityServerClient.authenticatePrincipal(SecurityServerClient.java:38)
at com.atlassian.crowd.integration.http.HttpAuthenticator.authenticate(HttpAuthenticator.java:259)
at com.atlassian.crowd.console.action.Login.execute(Login.java:66)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at com.opensymphony.xwork.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:358)
at com.opensymphony.xwork.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:218)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:192)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.interceptor.AroundInterceptor.intercept(AroundInterceptor.java:31)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.atlassian.crowd.console.interceptor.XWorkTransactionInterceptor.intercept(XWorkTransactionInterceptor.java:111)
at com.opensymphony.xwork.DefaultActionInvocation.invoke(DefaultActionInvocation.java:190)
at com.opensymphony.xwork.DefaultActionProxy.execute(DefaultActionProxy.java:116)
at com.opensymphony.webwork.dispatcher.DispatcherUtils.serviceAction(DispatcherUtils.java:273)
at com.opensymphony.webwork.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:202)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.opensymphony.module.sitemesh.filter.PageFilter.parsePage(PageFilter.java:118)
at com.opensymphony.module.sitemesh.filter.PageFilter.doFilter(PageFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.opensymphony.webwork.dispatcher.ActionContextCleanUp.doFilter(ActionContextCleanUp.java:88)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:75)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.core.filters.gzip.GzipFilter.doFilter(GzipFilter.java:55)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.core.filters.AbstractEncodingFilter.doFilter(AbstractEncodingFilter.java:33)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:199)
at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:282)
at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:767)
at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:697)
at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:889)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
at java.lang.Thread.run(Thread.java:595)

Referer : https://devsuite-test.atlassian.com/crowd/console/login.action

Build Information :
Version : 1.2.0 (Build:#190 - Nov 27, 2007)

Memory Information :
Total Memory : 64 MB
Free Memory : 11 MB
Used Memory : 52 MB

Request Information :

• Request URL : https://devsuite-test.atlassian.com/crowd/console/500.jsp
• Scheme : https
• Server : devsuite-test.atlassian.com
• Port : 443
• URI : /crowd/console/500.jsp
• Context Path : /crowd
• - Servlet Path : /console/500.jsp
• - Path Info : null
• - Query String :

Request Attributes :

• javax.servlet.forward.request_uri : /crowd/console/login.action
• javax.servlet.forward.context_path : /crowd
• javax.servlet.forward.servlet_path : /console/login.action
• javax.servlet.forward.path_info : /console/500.jsp
• javax.servlet.error.servlet_name : default
• javax.servlet.error.message :
• javax.servlet.error.exception : javax.servlet.ServletException: Could not invoke service.. Nested exception is org.codehaus.xfire.fault.XFireFault: Index: 0, Size: 0
• webwork.valueStack : com.opensymphony.xwork.util.OgnlValueStack@1d969a5
• javax.servlet.error.request_uri : /crowd/console/login.action
• __cleanup_counter : 0
• javax.servlet.error.status_code : 500
• _sitemesh_filterapplied : true
• sessioninview.FILTERED : true
• com.atlassian.core.filters.gzip.GzipFilter_already_filtered : true