SEVERE: Failed to read labels
java.lang.NullPointerException
	at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1960)
	at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1887)
	at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1770)
	at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1346)
	at java.io.ObjectInputStream.readObject(ObjectInputStream.java:368)
	at hudson.remoting.MultiClassLoaderSerializer$Input.readClassLoader(MultiClassLoaderSerializer.java:82)
	at hudson.remoting.MultiClassLoaderSerializer$Input.resolveProxyClass(MultiClassLoaderSerializer.java:102)
	at java.io.ObjectInputStream.readProxyDesc(ObjectInputStream.java:1548)
	at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1510)
	at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1749)
	at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1346)
	at java.io.ObjectInputStream.readObject(ObjectInputStream.java:368)
	at hudson.remoting.MultiClassLoaderSerializer$Input.readClassLoader(MultiClassLoaderSerializer.java:82)
	at hudson.remoting.MultiClassLoaderSerializer$Input.resolveClass(MultiClassLoaderSerializer.java:94)
	at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1592)
	at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1513)
	at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1749)
	at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1346)
	at java.io.ObjectInputStream.readObject(ObjectInputStream.java:368)
	at hudson.remoting.UserRequest.deserialize(UserRequest.java:169)
	at hudson.remoting.UserRequest.perform(UserRequest.java:88)
	at hudson.remoting.UserRequest.perform(UserRequest.java:48)
	at hudson.remoting.Request$2.run(Request.java:236)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
	at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
	at java.util.concurrent.FutureTask.run(FutureTask.java:166)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
	at hudson.remoting.Engine$1$1.run(Engine.java:54)
	at java.lang.Thread.run(Thread.java:636)