Jenkins gives me blank page

Question

I am getting this error when i start jenkins, which I believe is causing the jenkins to not work. Jenkins page comes up blank. I think the scm-sync-configuration is causing this to happen. It there anyway to workaround this or disable this plugin?

Running from: /Applications/Jenkins/jenkins.war
webroot: $user.home/.jenkins
Feb 08, 2016 12:30:13 PM winstone.Logger logInternal
INFO: Beginning extraction from war file
Feb 08, 2016 12:30:13 PM org.eclipse.jetty.util.log.JavaUtilLog info
INFO: jetty-winstone-2.9
Feb 08, 2016 12:30:14 PM org.eclipse.jetty.util.log.JavaUtilLog info
INFO: NO JSP Support for , did not find org.apache.jasper.servlet.JspServlet
Jenkins home directory: /Users/sss/.jenkins found at: $user.home/.jenkins
Feb 08, 2016 12:30:16 PM org.eclipse.jetty.util.log.JavaUtilLog info
INFO: Started [email protected]:8080
Feb 08, 2016 12:30:16 PM winstone.Logger logInternal
INFO: Winstone Servlet Engine v2.0 running: controlPort=disabled
Feb 08, 2016 12:30:16 PM jenkins.InitReactorRunner$1 onAttained
INFO: Started initialization
Feb 08, 2016 12:30:16 PM jenkins.InitReactorRunner$1 onAttained
INFO: Listed all plugins
Feb 08, 2016 12:30:17 PM hudson.plugins.scm_sync_configuration.SCMManipulator scmConfigurationSettledUp
INFO: Creating scmRepository connection data ..
Feb 08, 2016 12:30:17 PM hudson.plugins.scm_sync_configuration.scms.ScmSyncSubversionSCM extractScmCredentials
INFO: Extracting SVN Credentials for url : https://svn.aaa.com/
Feb 08, 2016 12:30:17 PM jenkins.InitReactorRunner$1 onTaskFailed
SEVERE: Failed Loading plugin scm-sync-configuration
java.io.IOException: Failed to initialize
    at hudson.ClassicPluginStrategy.load(ClassicPluginStrategy.java:441)
    at hudson.PluginManager$2$1$1.run(PluginManager.java:384)
    at org.jvnet.hudson.reactor.TaskGraphBuilder$TaskImpl.run(TaskGraphBuilder.java:169)
    at org.jvnet.hudson.reactor.Reactor.runTask(Reactor.java:282)
    at jenkins.model.Jenkins$8.runTask(Jenkins.java:913)
    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(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
    at sun.reflect.UnsafeFieldAccessorImpl.ensureObj(UnsafeFieldAccessorImpl.java:57)
    at sun.reflect.UnsafeQualifiedObjectFieldAccessorImpl.get(UnsafeQualifiedObjectFieldAccessorImpl.java:38)
    at java.lang.reflect.Field.get(Field.java:393)
    at hudson.plugins.scm_sync_configuration.scms.ScmSyncSubversionSCM.extractScmCredentials(ScmSyncSubversionSCM.java:59)
    at hudson.plugins.scm_sync_configuration.scms.SCM.getConfiguredRepository(SCM.java:66)
    at hudson.plugins.scm_sync_configuration.SCMManipulator.scmConfigurationSettledUp(SCMManipulator.java:57)
    at hudson.plugins.scm_sync_configuration.ScmSyncConfigurationBusiness.initializeRepository(ScmSyncConfigurationBusiness.java:72)
    at hudson.plugins.scm_sync_configuration.ScmSyncConfigurationBusiness.init(ScmSyncConfigurationBusiness.java:67)
    at hudson.plugins.scm_sync_configuration.ScmSyncConfigurationPlugin.initialInit(ScmSyncConfigurationPlugin.java:174)
    at hudson.plugins.scm_sync_configuration.ScmSyncConfigurationPlugin.start(ScmSyncConfigurationPlugin.java:157)
    at hudson.ClassicPluginStrategy.startPlugin(ClassicPluginStrategy.java:449)
    at hudson.ClassicPluginStrategy.load(ClassicPluginStrategy.java:438)
    ... 9 more
Feb 08, 2016 12:30:17 PM jenkins.InitReactorRunner$1 onAttained
INFO: Prepared all plugins
Feb 08, 2016 12:30:17 PM jenkins.InitReactorRunner$1 onAttained
INFO: Started all plugins
Feb 08, 2016 12:30:17 PM jenkins.InitReactorRunner$1 onAttained
INFO: Augmented all extensions
Feb 08, 2016 12:30:20 PM jenkins.InitReactorRunner$1 onAttained
INFO: Loaded all jobs
Feb 08, 2016 12:30:20 PM hudson.model.AsyncPeriodicWork$1 run
INFO: Started Download metadata
Feb 08, 2016 12:30:20 PM hudson.model.AsyncPeriodicWork$1 run
INFO: Finished Download metadata. 2 ms
Feb 08, 2016 12:30:21 PM org.jenkinsci.main.modules.sshd.SSHD start
INFO: Started SSHD at port 49295
Feb 08, 2016 12:30:21 PM jenkins.InitReactorRunner$1 onAttained
INFO: Completed initialization
Feb 08, 2016 12:30:21 PM hudson.UDPBroadcastThread run
INFO: Cannot listen to UDP port 33,848, skipping: java.net.SocketException: Can't assign requested address
Feb 08, 2016 12:30:21 PM jenkins.InitReactorRunner$1 onAttained
INFO: Started initialization
Feb 08, 2016 12:30:21 PM jenkins.InitReactorRunner$1 onAttained
INFO: Listed all plugins
Feb 08, 2016 12:30:21 PM jenkins.InitReactorRunner$1 onAttained
INFO: Prepared all plugins
Feb 08, 2016 12:30:21 PM jenkins.InitReactorRunner$1 onAttained
INFO: Started all plugins
Feb 08, 2016 12:30:21 PM jenkins.InitReactorRunner$1 onAttained
INFO: Augmented all extensions
Feb 08, 2016 12:30:21 PM jenkins.InitReactorRunner$1 onAttained
INFO: Loaded all jobs
Feb 08, 2016 12:30:21 PM jenkins.InitReactorRunner$1 onAttained
INFO: Completed initialization
Feb 08, 2016 12:30:21 PM hudson.WebAppMain$3 run
INFO: Jenkins is fully up and running

Answer 1

I was also facing the same issue after I installed Jenkins and tried to login. http://localhost:8080/restart

Open this URL. This will restart the Jenkins and it would be fine. Note: Edit the port number as per your installation.

Answer 2

You can disable the plugin by modifying the plugins directory. Have a look here.

https://wiki.jenkins-ci.org/display/JENKINS/Removing+and+disabling+plugins