This afternoon I updated via the plugin manager 

• subversion
• script-security
• ssh-slaves
• jackson2-api
• scm-api
• docker-commons

*Note we use the collabnet authorization plugin

After doing so Jenkins will not start back up citing the following error:

com.thoughtworks.xstream.mapper.CannotResolveClassException: hudson.plugins.collabnet.auth.CNAuthorizationStrategy at com.thoughtworks.xstream.mapper.DefaultMapper.realClass(DefaultMapper.java:79) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.DynamicProxyMapper.realClass(DynamicProxyMapper.java:55) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.PackageAliasingMapper.realClass(PackageAliasingMapper.java:88) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.ClassAliasingMapper.realClass(ClassAliasingMapper.java:79) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.ArrayMapper.realClass(ArrayMapper.java:74) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.SecurityMapper.realClass(SecurityMapper.java:71) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at hudson.util.XStream2$CompatibilityMapper.realClass(XStream2.java:285) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at hudson.util.xstream.MapperDelegate.realClass(MapperDelegate.java:43) at com.thoughtworks.xstream.mapper.MapperWrapper.realClass(MapperWrapper.java:30) at com.thoughtworks.xstream.mapper.CachingMapper.realClass(CachingMapper.java:48) at hudson.util.RobustReflectionConverter.determineType(RobustReflectionConverter.java:461) at hudson.util.RobustReflectionConverter.doUnmarshal(RobustReflectionConverter.java:327) Caused: jenkins.util.xstream.CriticalXStreamException: hudson.plugins.collabnet.auth.CNAuthorizationStrategy : hudson.plugins.collabnet.auth.CNAuthorizationStrategy ---- Debugging information ---- message : hudson.plugins.collabnet.auth.CNAuthorizationStrategy cause-exception : com.thoughtworks.xstream.mapper.CannotResolveClassException cause-message : hudson.plugins.collabnet.auth.CNAuthorizationStrategy class : hudson.model.Hudson required-type : hudson.model.Hudson converter-type : hudson.util.RobustReflectionConverter path : /hudson/authorizationStrategy line number : 8 version : not available ------------------------------- at hudson.util.RobustReflectionConverter.doUnmarshal(RobustReflectionConverter.java:356) at hudson.util.RobustReflectionConverter.unmarshal(RobustReflectionConverter.java:270) at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:72) at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:65) at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:66) at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:50) at com.thoughtworks.xstream.core.TreeUnmarshaller.start(TreeUnmarshaller.java:134) at com.thoughtworks.xstream.core.AbstractTreeMarshallingStrategy.unmarshal(AbstractTreeMarshallingStrategy.java:32) at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1189) at hudson.util.XStream2.unmarshal(XStream2.java:114) at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:1173) at hudson.XmlFile.unmarshal(XmlFile.java:167) Caused: java.io.IOException: Unable to read E:\Program Files (x86)\Jenkins\config.xml at hudson.XmlFile.unmarshal(XmlFile.java:169) at jenkins.model.Jenkins.loadConfig(Jenkins.java:3063) at jenkins.model.Jenkins.access$1200(Jenkins.java:304) at jenkins.model.Jenkins$14.run(Jenkins.java:3081) at org.jvnet.hudson.reactor.TaskGraphBuilder$TaskImpl.run(TaskGraphBuilder.java:169) at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:282) at jenkins.model.Jenkins$5.runTask(Jenkins.java:1065) at org.jvnet.hudson.reactor.Reactor$2.run(Reactor.java:210) at org.jvnet.hudson.reactor.Reactor$Node.run(Reactor.java:117) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source) Caused: org.jvnet.hudson.reactor.ReactorException at org.jvnet.hudson.reactor.Reactor.execute(Reactor.java:269) at jenkins.InitReactorRunner.run(InitReactorRunner.java:47) at jenkins.model.Jenkins.executeReactor(Jenkins.java:1099) at jenkins.model.Jenkins.<init>(Jenkins.java:904) at hudson.model.Hudson.<init>(Hudson.java:86) at hudson.model.Hudson.<init>(Hudson.java:82) at hudson.WebAppMain$3.run(WebAppMain.java:233) Caused: hudson.util.HudsonFailedToLoad at hudson.WebAppMain$3.run(WebAppMain.java:250)