title: Neo4j Server Startup Exception
body: <p>Iam unable to start the neo4j server..iam using java 1.7 and neo4j 2.0.0 when i run the sample java with maven example, iam getting this problem. Here is the log file </p>
  
  <pre><code>Oct 09, 2013 8:49:14 AM org.neo4j.server.logging.Logger log
  INFO: Setting startup timeout to: 120000ms based on -1
  Oct 09, 2013 8:49:15 AM org.neo4j.server.logging.Logger log
  SEVERE: 
  org.neo4j.server.ServerStartupException: Starting Neo4j Server failed: org.neo4j.kernel.lifecycle.LifecycleException: Component 'org.neo4j.kernel.impl.transaction.XaDataSourceManager@ce8273' was successfully initialized, but failed to start. Please see attached cause exception.
      at org.neo4j.server.AbstractNeoServer.start(AbstractNeoServer.java:211)
      at org.neo4j.server.Bootstrapper.start(Bootstrapper.java:86)
      at org.neo4j.server.Bootstrapper.main(Bootstrapper.java:49)
  Caused by: java.lang.RuntimeException: org.neo4j.kernel.lifecycle.LifecycleException: Component 'org.neo4j.kernel.impl.transaction.XaDataSourceManager@ce8273' was successfully initialized, but failed to start. Please see attached cause exception.
      at org.neo4j.kernel.InternalAbstractGraphDatabase.run(InternalAbstractGraphDatabase.java:280)
      at org.neo4j.kernel.EmbeddedGraphDatabase.&lt;init&gt;(EmbeddedGraphDatabase.java:106)
      at org.neo4j.graphdb.factory.GraphDatabaseFactory$1.newDatabase(GraphDatabaseFactory.java:88)
      at org.neo4j.graphdb.factory.GraphDatabaseBuilder.newGraphDatabase(GraphDatabaseBuilder.java:207)
      at org.neo4j.kernel.impl.recovery.StoreRecoverer.recover(StoreRecoverer.java:114)
      at org.neo4j.server.preflight.PerformRecoveryIfNecessary.run(PerformRecoveryIfNecessary.java:59)
      at org.neo4j.server.preflight.PreFlightTasks.run(PreFlightTasks.java:70)
      at org.neo4j.server.AbstractNeoServer.runPreflightTasks(AbstractNeoServer.java:276)
      at org.neo4j.server.AbstractNeoServer.start(AbstractNeoServer.java:162)
      ... 2 more
  Caused by: org.neo4j.kernel.lifecycle.LifecycleException: Component 'org.neo4j.kernel.impl.transaction.XaDataSourceManager@ce8273' was successfully initialized, but failed to start. Please see attached cause exception.
      at org.neo4j.kernel.lifecycle.LifeSupport$LifecycleInstance.start(LifeSupport.java:497)
      at org.neo4j.kernel.lifecycle.LifeSupport.start(LifeSupport.java:104)
      at org.neo4j.kernel.InternalAbstractGraphDatabase.run(InternalAbstractGraphDatabase.java:258)
      ... 10 more
  Caused by: org.neo4j.kernel.lifecycle.LifecycleException: Component 'org.neo4j.kernel.impl.nioneo.xa.NeoStoreXaDataSource@1f5329f' was successfully initialized, but failed to start. Please see attached cause exception.
      at org.neo4j.kernel.lifecycle.LifeSupport$LifecycleInstance.start(LifeSupport.java:497)
      at org.neo4j.kernel.lifecycle.LifeSupport.start(LifeSupport.java:104)
      at org.neo4j.kernel.impl.transaction.XaDataSourceManager.start(XaDataSourceManager.java:128)
      at org.neo4j.kernel.lifecycle.LifeSupport$LifecycleInstance.start(LifeSupport.java:491)
      ... 12 more
  Caused by: org.neo4j.kernel.impl.storemigration.UpgradeNotAllowedByConfigurationException: Failed to start Neo4j with an older data store version. To enable automatic upgrade, please set configuration parameter "allow_store_upgrade=true"
      at org.neo4j.kernel.impl.storemigration.ConfigMapUpgradeConfiguration.checkConfigurationAllowsAutomaticUpgrade(ConfigMapUpgradeConfiguration.java:39)
      at org.neo4j.kernel.impl.storemigration.StoreUpgrader.attemptUpgrade(StoreUpgrader.java:66)
      at org.neo4j.kernel.impl.nioneo.store.StoreFactory.tryToUpgradeStores(StoreFactory.java:113)
      at org.neo4j.kernel.impl.nioneo.store.StoreFactory.newNeoStore(StoreFactory.java:96)
      at org.neo4j.kernel.impl.nioneo.xa.NeoStoreXaDataSource.start(NeoStoreXaDataSource.java:240)
      at org.neo4j.kernel.lifecycle.LifeSupport$LifecycleInstance.start(LifeSupport.java:491)
      ... 15 more
  
  Oct 09, 2013 8:49:15 AM org.neo4j.server.logging.Logger log
  SEVERE: Failed to start Neo Server on port [7474]
  </code></pre>
  
  <p>How to clear this?</p>