Eclipse Juno unable to open my workspace after the plugin update

Question

Just I got update the plugin in eclipse juno.

More specifically the GWT 2.5 development plugin.

After I installed in it successfully,and its asked for restart.After that it exits and when tried to restart got an error

"Unable to open the workbench,see the error logs"

Sorry for dumping all the Exception from Logs,i did'nt find any clues here.

!SESSION 2013-08-15 16:00:26.913 -----------------------------------------------
eclipse.buildId=I20121031-2000
java.version=1.7.0_25
java.vendor=Oracle Corporation
BootLoader constants: OS=win32, ARCH=x86, WS=win32, NL=en_US
Framework arguments:  -product org.eclipse.epp.package.java.product
Command-line arguments:  -os win32 -ws win32 -arch x86 -product org.eclipse.epp.package.java.product

!ENTRY org.eclipse.e4.ui.workbench 4 0 2013-08-15 16:00:29.745
!MESSAGE Unable to create class 'org.eclipse.e4.core.commands.CommandServiceAddon' from bundle '85'
!STACK 0
org.eclipse.e4.core.di.InjectionException: java.lang.ClassCastException: Cannot cast org.eclipse.core.commands.CommandManager to org.eclipse.core.commands.CommandManager
    at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:63)
    at org.eclipse.e4.core.internal.di.InjectorImpl.processAnnotated(InjectorImpl.java:861)
    at org.eclipse.e4.core.internal.di.InjectorImpl.inject(InjectorImpl.java:113)
    at org.eclipse.e4.core.internal.di.InjectorImpl.internalMake(InjectorImpl.java:321)
    at org.eclipse.e4.core.internal.di.InjectorImpl.make(InjectorImpl.java:255)
    at org.eclipse.e4.core.contexts.ContextInjectionFactory.make(ContextInjectionFactory.java:185)
    at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.createFromBundle(ReflectionContributionFactory.java:105)
    at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.doCreate(ReflectionContributionFactory.java:71)
    at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.create(ReflectionContributionFactory.java:49)
    at org.eclipse.e4.ui.internal.workbench.swt.E4Application.createE4Workbench(E4Application.java:258)
    at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:556)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
    at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:542)
    at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
    at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:124)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:353)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:180)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1438)
Caused by: java.lang.ClassCastException: Cannot cast org.eclipse.core.commands.CommandManager to org.eclipse.core.commands.CommandManager
    at java.lang.Class.cast(Unknown Source)
    at org.eclipse.e4.core.internal.contexts.EclipseContext.get(EclipseContext.java:557)
    at org.eclipse.e4.core.commands.CommandServiceAddon.init(CommandServiceAddon.java:30)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:56)
    ... 26 more

!ENTRY org.eclipse.e4.ui.workbench 4 0 2013-08-15 16:00:29.753
!MESSAGE Unable to create class 'org.eclipse.e4.ui.internal.workbench.addons.CommandProcessingAddon' from bundle '98'
!STACK 0
org.eclipse.e4.core.di.InjectionException: Unable to process "CommandProcessingAddon.commandService": no actual value was found for the argument "ECommandService".
    at org.eclipse.e4.core.internal.di.InjectorImpl.reportUnresolvedArgument(InjectorImpl.java:396)
    at org.eclipse.e4.core.internal.di.InjectorImpl.resolveRequestorArgs(InjectorImpl.java:387)
    at org.eclipse.e4.core.internal.di.InjectorImpl.inject(InjectorImpl.java:102)
    at org.eclipse.e4.core.internal.di.InjectorImpl.internalMake(InjectorImpl.java:321)
    at org.eclipse.e4.core.internal.di.InjectorImpl.make(InjectorImpl.java:255)
    at org.eclipse.e4.core.contexts.ContextInjectionFactory.make(ContextInjectionFactory.java:185)
    at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.createFromBundle(ReflectionContributionFactory.java:105)
    at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.doCreate(ReflectionContributionFactory.java:71)
    at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.create(ReflectionContributionFactory.java:49)
    at org.eclipse.e4.ui.internal.workbench.swt.E4Application.createE4Workbench(E4Application.java:258)
    at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:556)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
    at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:542)
    at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
    at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:124)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:353)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:180)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1438)

!ENTRY org.eclipse.e4.ui.workbench 4 0 2013-08-15 16:00:29.758
!MESSAGE Unable to create class 'org.eclipse.e4.ui.workbench.swt.util.BindingProcessingAddon' from bundle '101'
!STACK 0
org.eclipse.e4.core.di.InjectionException: Unable to process "BindingProcessingAddon.commandService": no actual value was found for the argument "ECommandService".
    at org.eclipse.e4.core.internal.di.InjectorImpl.reportUnresolvedArgument(InjectorImpl.java:396)
    at org.eclipse.e4.core.internal.di.InjectorImpl.resolveRequestorArgs(InjectorImpl.java:387)
    at org.eclipse.e4.core.internal.di.InjectorImpl.inject(InjectorImpl.java:102)
    at org.eclipse.e4.core.internal.di.InjectorImpl.internalMake(InjectorImpl.java:321)
    at org.eclipse.e4.core.internal.di.InjectorImpl.make(InjectorImpl.java:255)
    at org.eclipse.e4.core.contexts.ContextInjectionFactory.make(ContextInjectionFactory.java:185)
    at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.createFromBundle(ReflectionContributionFactory.java:105)
    at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.doCreate(ReflectionContributionFactory.java:71)
    at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.create(ReflectionContributionFactory.java:49)
    at org.eclipse.e4.ui.internal.workbench.swt.E4Application.createE4Workbench(E4Application.java:258)
    at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:556)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
    at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:542)
    at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
    at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:124)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:353)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:180)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1438)

Answer 1

Problems with Eclipse's workspaces tend to be painful. Try going to your installation path, and find configuration\org.eclipse.equinox.simpleconfigurator\.

Open bundles.info and then delete the lower version of duplicate entry for org.eclipse.core.commands. Then restart the eclipse with the -clean option.