in org.compass.core.lucene.engine.store.FSDirectoryStore.configure(CompassSettings settings) if (!directory.getClass().getName().equals(getFSDirectoryClass())) { throw new SearchEngineException("Setting type of FS directory is a JVM " + "level setting, you can not set different values within the same JVM"); } cause by lucence2.9.0 directory.getClass() return org.apache.lucene.store.SimpleFSDirectory not org.apache.lucene.store.FSDirectory BTW: why need such restriction?