I chose automatic upgrade to 1.417, but unchecked automatic restart. Once download/installation has completed, it is no longer possible to enter Manage Jenkins webpage - it throws:

org.apache.commons.jelly.JellyTagException: jar:file:/cplatform/cp_hudson/hudson/war/WEB-INF/lib/jenkins-core-1.416.jar!/hudson/model/UpdateCenter/CoreUpdateMonitor/message.jelly:31:46: can't parse argument number rootURL
at org.apache.commons.jelly.impl.TagScript.handleException(TagScript.java:709)
at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:282)
at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:161)
at org.apache.commons.jelly.tags.core.ChooseTag.doTag(ChooseTag.java:38)
at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:270)
at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
at org.kohsuke.stapler.jelly.ReallyStaticTagLibrary$1.run(ReallyStaticTagLibrary.java:99)
at org.apache.commons.jelly.tags.core.CoreTagLibrary$2.run(CoreTagLibrary.java:105)
at org.kohsuke.stapler.jelly.JellyViewScript.run(JellyViewScript.java:63)
at org.kohsuke.stapler.jelly.IncludeTag.doTag(IncludeTag.java:146)
at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:270)
at org.apache.commons.jelly.tags.core.CoreTagLibrary$1.run(CoreTagLibrary.java:98)
at org.apache.commons.jelly.TagSupport.invokeBody(TagSupport.java:161)
at org.apache.commons.jelly.tags.core.ForEachTag.doTag(ForEachTag.java:150)
at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:270)
at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
at org.kohsuke.stapler.jelly.CallTagLibScript$1.run(CallTagLibScript.java:98)
at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag(InvokeBodyTag.java:91)
at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:270)
at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
at org.apache.commons.jelly.tags.core.CoreTagLibrary$1.run(CoreTagLibrary.java:98)
at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
at org.apache.commons.jelly.tags.core.CoreTagLibrary$2.run(CoreTagLibrary.java:105)
at org.kohsuke.stapler.jelly.CallTagLibScript.run(CallTagLibScript.java:119)
at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
at org.kohsuke.stapler.jelly.CallTagLibScript$1.run(CallTagLibScript.java:98)
at org.apache.commons.jelly.tags.define.InvokeBodyTag.doTag(InvokeBodyTag.java:91)
at org.apache.commons.jelly.impl.TagScript.run(TagScript.java:270)
at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
at org.kohsuke.stapler.jelly.ReallyStaticTagLibrary$1.run(ReallyStaticTagLibrary.java:99)
at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
at org.kohsuke.stapler.jelly.ReallyStaticTagLibrary$1.run(ReallyStaticTagLibrary.java:99)
at org.kohsuke.stapler.jelly.ReallyStaticTagLibrary$1.run(ReallyStaticTagLibrary.java:99)
at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
at org.kohsuke.stapler.jelly.ReallyStaticTagLibrary$1.run(ReallyStaticTagLibrary.java:99)
at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
at org.kohsuke.stapler.jelly.ReallyStaticTagLibrary$1.run(ReallyStaticTagLibrary.java:99)
at org.apache.commons.jelly.impl.ScriptBlock.run(ScriptBlock.java:95)
at org.apache.commons.jelly.tags.core.CoreTagLibrary$2.run(CoreTagLibrary.java:105)
at org.kohsuke.stapler.jelly.CallTagLibScript.run(CallTagLibScript.java:119)
at org.apache.commons.jelly.tags.core.CoreTagLibrary$2.run(CoreTagLibrary.java:105)
at org.kohsuke.stapler.jelly.JellyViewScript.run(JellyViewScript.java:63)
at org.kohsuke.stapler.jelly.DefaultScriptInvoker.invokeScript(DefaultScriptInvoker.java:63)
at org.kohsuke.stapler.jelly.DefaultScriptInvoker.invokeScript(DefaultScriptInvoker.java:53)
at org.kohsuke.stapler.jelly.JellyFacet$1.dispatch(JellyFacet.java:89)
at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:561)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:646)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:477)
at org.kohsuke.stapler.Stapler.service(Stapler.java:159)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:45)
at winstone.ServletConfiguration.execute(ServletConfiguration.java:249)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:335)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:378)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:94)
at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:86)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:195)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:368)
at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:85)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:195)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:368)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:84)
at hudson.security.UnwrapSecurityExceptionFilter.doFilter(UnwrapSecurityExceptionFilter.java:51)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.ui.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:166)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.providers.anonymous.AnonymousProcessingFilter.doFilter(AnonymousProcessingFilter.java:125)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.ui.rememberme.RememberMeProcessingFilter.doFilter(RememberMeProcessingFilter.java:142)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:271)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.ui.basicauth.BasicProcessingFilter.doFilter(BasicProcessingFilter.java:173)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:249)
at hudson.security.HttpSessionContextIntegrationFilter2.doFilter(HttpSessionContextIntegrationFilter2.java:66)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:164)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:195)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:368)
at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:81)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:195)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:368)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:333)
at winstone.RequestHandlerThread.processRequest(RequestHandlerThread.java:244)
at winstone.RequestHandlerThread.run(RequestHandlerThread.java:150)
at java.lang.Thread.run(Thread.java:619)