Error after seleting "Versionsplanung" on project page

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Details: ------- java.lang.NullPointerException at org.apache.lucene.index.IndexReader.open(IndexReader.java:110) at org.apache.lucene.index.IndexReader.open(IndexReader.java:106) at com.atlassian.jira.web.filters.ThreadLocalQueryProfiler.retrieveReader(ThreadLocalQueryProfiler.java:184) at com.atlassian.jira.web.filters.ThreadLocalQueryProfiler.retrieveSearcher(ThreadLocalQueryProfiler.java:172) at com.atlassian.jira.web.filters.ThreadLocalQueryProfiler.getSearcher(ThreadLocalQueryProfiler.java:61) at com.atlassian.jira.issue.search.SearchProviderFactoryImpl.getSearcher(SearchProviderFactoryImpl.java:18) at com.atlassian.jira.issue.search.providers.LuceneSearchProvider.getHits(LuceneSearchProvider.java:60) at com.atlassian.jira.issue.search.providers.LuceneSearchProvider.search(LuceneSearchProvider.java:175) at com.atlassian.jira.web.action.browser.Browser.getIssuesByFixForVersion(Browser.java:186) at com.atlassian.jira.web.action.browser.Browser.getIssueSummaryByFixForVersion(Browser.java:197) 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 org.apache.velocity.util.introspection.UberspectImpl$VelMethodImpl.invoke(UberspectImpl.java:267) at org.apache.velocity.runtime.parser.node.ASTMethod.execute(ASTMethod.java:197) at org.apache.velocity.runtime.parser.node.ASTReference.execute(ASTReference.java:175) at org.apache.velocity.runtime.parser.node.ASTReference.value(ASTReference.java:327) at org.apache.velocity.runtime.parser.node.ASTExpression.value(ASTExpression.java:51) at org.apache.velocity.runtime.parser.node.ASTSetDirective.render(ASTSetDirective.java:95) at org.apache.velocity.runtime.parser.node.ASTBlock.render(ASTBlock.java:55) at org.apache.velocity.runtime.parser.node.ASTIfStatement.render(ASTIfStatement.java:70) at org.apache.velocity.runtime.parser.node.ASTBlock.render(ASTBlock.java:55) at org.apache.velocity.runtime.directive.Foreach.render(Foreach.java:166) at org.apache.velocity.runtime.parser.node.ASTDirective.render(ASTDirective.java:114) at org.apache.velocity.runtime.parser.node.ASTBlock.render(ASTBlock.java:55) at org.apache.velocity.runtime.parser.node.ASTIfStatement.render(ASTIfStatement.java:70) at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:230) at org.apache.velocity.Template.merge(Template.java:256) at org.apache.velocity.app.VelocityEngine.mergeTemplate(VelocityEngine.java:450) at com.atlassian.velocity.DefaultVelocityManager.getEncodedBody(DefaultVelocityManager.java:76) at com.atlassian.velocity.DefaultVelocityManager.getEncodedBody(DefaultVelocityManager.java:60) at com.atlassian.velocity.DefaultVelocityManager.getEncodedBody(DefaultVelocityManager.java:55) at com.atlassian.jira.plugin.JiraResourcedModuleDescriptor.getHtml(JiraResourcedModuleDescriptor.java:97) at com.atlassian.jira.plugin.projectpanel.impl.GenericProjectTabPanel.getHtml(GenericProjectTabPanel.java:25) at com.atlassian.jira.web.action.browser.Browser.getProjectTabHtml(Browser.java:337) 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 webwork.util.InjectionUtils$DefaultInjectionImpl.invoke(InjectionUtils.java:61) at webwork.util.InjectionUtils.invoke(InjectionUtils.java:52) at webwork.util.ValueStack.findValue(ValueStack.java:426) at webwork.util.ValueStack.findValue(ValueStack.java:175) at webwork.view.taglib.WebWorkBodyTagSupport.findValue(WebWorkBodyTagSupport.java:61) at webwork.view.taglib.BasicPropertyTag.doStartTag(BasicPropertyTag.java:54) at org.apache.jsp.includes.panels.browser.tabpanels_jsp._jspx_meth_webwork_property_7(org.apache.jsp.includes.panels.browser.tabpanels_jsp:753) at org.apache.jsp.includes.panels.browser.tabpanels_jsp._jspx_meth_webwork_else_3(org.apache.jsp.includes.panels.browser.tabpanels_jsp:728) at org.apache.jsp.includes.panels.browser.tabpanels_jsp._jspService(org.apache.jsp.includes.panels.browser.tabpanels_jsp:296) at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97) at javax.servlet.http.HttpServlet.service(HttpServlet.java:802) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:322) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:291) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241) at javax.servlet.http.HttpServlet.service(HttpServlet.java:802) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:672) at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:574) at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:499) at org.apache.jasper.runtime.JspRuntimeLibrary.include(JspRuntimeLibrary.java:966) at org.apache.jsp.secure.views.browser.browseproject_jsp._jspService(org.apache.jsp.secure.views.browser.browseproject_jsp:343) at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97) at javax.servlet.http.HttpServlet.service(HttpServlet.java:802) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:322) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:291) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241) at javax.servlet.http.HttpServlet.service(HttpServlet.java:802) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:672) at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:463) at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:398) at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:301) at com.atlassian.jira.web.dispatcher.JiraServletDispatcher.service(JiraServletDispatcher.java:253) at javax.servlet.http.HttpServlet.service(HttpServlet.java:802) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:672) at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:463) at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:398) at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:301) at com.atlassian.jira.servlet.QuickLinkServlet.service(QuickLinkServlet.java:76) at javax.servlet.http.HttpServlet.service(HttpServlet.java:802) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at com.atlassian.jira.web.filters.AccessLogFilter.doFilter(AccessLogFilter.java:51) 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:119) at com.opensymphony.module.sitemesh.filter.PageFilter.doFilter(PageFilter.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.seraph.filter.SecurityFilter.doFilter(SecurityFilter.java:182) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at com.atlassian.seraph.filter.LoginFilter.doFilter(LoginFilter.java:181) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at com.atlassian.util.profiling.filters.ProfilingFilter.doFilter(ProfilingFilter.java:132) at com.atlassian.jira.web.filters.ProfilingAndErrorFilter.doFilter(ProfilingAndErrorFilter.java:35) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173) at com.atlassian.jira.web.filters.ActionCleanupDelayFilter.doFilter(ActionCleanupDelayFilter.java:39) 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:37) 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.coyote.http11.Http11Processor.process(Http11Processor.java:856) at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:744) at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527) at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684) at java.lang.Thread.run(Thread.java:595)