title: Eclipse crashed and won't restart. I don't understand the stack trace
body: <p>Eclipse crashed and won't restart.
  Can someone help me understand what the problem is? The message from the log is below.
  I am on Win7 and develop with Android SDKand I recently installed subclipse svn
  Thank you very much   </p>
  
  <pre><code>    !ENTRY org.eclipse.core.resources 4 566 2012-01-24 15:15:54.500
  !MESSAGE Cannot set lower sequence number for root (previous: 178, new: 177). Ignoring the new value.
  !STACK 0
  java.lang.IllegalArgumentException: Cannot set lower sequence number for root (previous: 178, new: 177). Ignoring the new value.
  at org.eclipse.core.internal.resources.SaveManager$MasterTable.put(SaveManager.java:50)
  at java.util.Properties.load0(Unknown Source)
  at java.util.Properties.load(Unknown Source)
  at org.eclipse.core.internal.resources.SaveManager.restoreMasterTable(SaveManager.java:829)
  at org.eclipse.core.internal.resources.SaveManager.restore(SaveManager.java:684)
  at org.eclipse.core.internal.resources.SaveManager.startup(SaveManager.java:1527)
  at org.eclipse.core.internal.resources.Workspace.startup(Workspace.java:2503)
  at org.eclipse.core.internal.resources.Workspace.open(Workspace.java:2251)
  at org.eclipse.core.resources.ResourcesPlugin.start(ResourcesPlugin.java:439)
  at org.eclipse.osgi.framework.internal.core.BundleContextImpl$1.run(BundleContextImpl.java:711)
  at java.security.AccessController.doPrivileged(Native Method)
  at org.eclipse.osgi.framework.internal.core.BundleContextImpl.startActivator(BundleContextImpl.java:702)
  at org.eclipse.osgi.framework.internal.core.BundleContextImpl.start(BundleContextImpl.java:683)
  at org.eclipse.osgi.framework.internal.core.BundleHost.startWorker(BundleHost.java:381)
  at org.eclipse.osgi.framework.internal.core.AbstractBundle.start(AbstractBundle.java:299)
  at org.eclipse.osgi.framework.util.SecureAction.start(SecureAction.java:440)
  at org.eclipse.osgi.internal.loader.BundleLoader.setLazyTrigger(BundleLoader.java:268)
  at org.eclipse.core.runtime.internal.adaptor.EclipseLazyStarter.postFindLocalClass(EclipseLazyStarter.java:107)
  at org.eclipse.osgi.baseadaptor.loader.ClasspathManager.findLocalClass(ClasspathManager.java:462)
  at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.findLocalClass(DefaultClassLoader.java:216)
  at org.eclipse.osgi.internal.loader.BundleLoader.findLocalClass(BundleLoader.java:400)
  at     org.eclipse.osgi.internal.loader.SingleSourcePackage.loadClass(SingleSourcePackage.java:35)
  at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:473)
  at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:429)
  at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:417)
  at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107)
  at java.lang.ClassLoader.loadClass(Unknown Source)
  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:344)
  at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
  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:622)
  at org.eclipse.equinox.launcher.Main.basicRun(Main.java:577)
  at org.eclipse.equinox.launcher.Main.run(Main.java:1410)
  at org.eclipse.equinox.launcher.Main.main(Main.java:1386)
  </code></pre>