Monitor plugin 1.5.6 does not work on OF 4.1.3

I upgraded the server to version 4.1.3.

When installing the monitoring plugin, I get an error in the error-log:

2017.04.30 16:48:27 org.jivesoftware.openfire.container.PluginManager - An exception occurred while loading plugin 'monitoring': org.picocontainer.PicoLifecycleException: PicoLifecycleException: method 'public abstract void org.picocontainer.Startable.start()', instance 'org.jivesoftware.openfire.archive.ArchiveIndexer@512eb371, null at org.picocontainer.monitors.DefaultComponentMonitor.lifecycleInvocationFailed(DefaultComponentMonitor.java:43) at org.picocontainer.defaults.DefaultLifecycleStrategy.start(DefaultLifecycleStrategy.java:49) at org.picocontainer.defaults.InstantiatingComponentAdapter.start(InstantiatingComponentAdapter.java:164) at org.picocontainer.defaults.DecoratingComponentAdapter.start(DecoratingComponentAdapter.java:154) at org.picocontainer.defaults.CachingComponentAdapter.start(CachingComponentAdapter.java:86) at org.picocontainer.defaults.DefaultPicoContainer$OrderedComponentAdapterLifecycleManager.start(DefaultPicoContainer.java:663) at org.picocontainer.defaults.DefaultPicoContainer.start(DefaultPicoContainer.java:464) at org.jivesoftware.openfire.plugin.MonitoringPlugin.initializePlugin(MonitoringPlugin.java:206) at org.jivesoftware.openfire.container.PluginManager.loadPlugin(PluginManager.java:407) at org.jivesoftware.openfire.container.PluginMonitor$MonitorTask$4.call(PluginMonitor.java:276) at org.jivesoftware.openfire.container.PluginMonitor$MonitorTask$4.call(PluginMonitor.java:264) at java.util.concurrent.FutureTask.run(FutureTask.java:262) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745) Caused by: java.lang.NullPointerException at org.apache.lucene.index.IndexReader.isLocked(IndexReader.java:1330) at org.jivesoftware.openfire.archive.ArchiveIndexer.start(ArchiveIndexer.java:144) at org.picocontainer.defaults.DefaultLifecycleStrategy.start(DefaultLifecycleStrategy.java:46) ... 13 more Caused by:

And no menu appears “Archiving messages”