Yes, there is many lines in servo.log file, but they don't help me to understand

2016-01-02 21:22:13,958 INFO [MediaServer] ------------------------------------------------------------------------
2016-01-02 21:22:14,003 INFO [MediaServer] Serviio DLNA media streaming server v 1.5.2 (rev. 4b9ce176daa1)
2016-01-02 21:22:14,003 INFO [MediaServer] Petr Nejedly 2009-2015
2016-01-02 21:22:14,003 INFO [MediaServer]
http://www.serviio.org2016-01-02 21:22:14,003 INFO [MediaServer]
2016-01-02 21:22:14,003 INFO [MediaServer] Java 1.8.0_40-Oracle Corporation x86_64
2016-01-02 21:22:14,003 INFO [MediaServer] OS Mac OS X 10.10.5
2016-01-02 21:22:14,003 INFO [MediaServer] File encoding: UTF-8
2016-01-02 21:22:14,004 INFO [MediaServer] Headless mode enabled: true
2016-01-02 21:22:14,004 INFO [MediaServer] User: root
2016-01-02 21:22:14,004 INFO [MediaServer] User home dir: /var/root
2016-01-02 21:22:14,004 INFO [MediaServer] Temp dir: /var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T/
2016-01-02 21:22:14,004 INFO [MediaServer] ------------------------------------------------------------------------
2016-01-02 21:22:14,129 INFO [WebServer] Socket buffer set to 65535 bytes
2016-01-02 21:22:14,129 INFO [RestletServer] Starting Restlet server (/rest) exposed on port 23423
2016-01-02 21:22:14,201 INFO [RestletServer] Starting Restlet server (/cds) exposed on port 23424
2016-01-02 21:22:14,201 INFO [RestletServer] Starting Restlet server (/mediabrowser) exposed on port 23424
2016-01-02 21:22:14,215 INFO [DBSchemaUpdateExecutor] Checking if DB schema needs to be updated
2016-01-02 21:22:14,223 INFO [DatabaseManager] Using DERBY database language
2016-01-02 21:22:14,426 WARN [DBConnectionPool] Can't create a new connection for jdbc:derby:db;create=true
java.sql.SQLException: Failed to create database 'db', see the next exception for details.
at org.apache.derby.impl.jdbc.SQLExceptionFactory.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.SQLExceptionFactory.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.seeNextException(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection.createDatabase(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection.<init>(Unknown Source)
at org.apache.derby.jdbc.InternalDriver.getNewEmbedConnection(Unknown Source)
at org.apache.derby.jdbc.InternalDriver.connect(Unknown Source)
at org.apache.derby.jdbc.InternalDriver.connect(Unknown Source)
at org.apache.derby.jdbc.AutoloadedDriver.connect(Unknown Source)
at java.sql.DriverManager.getConnection(DriverManager.java:664)
at java.sql.DriverManager.getConnection(DriverManager.java:270)
at org.serviio.db.DBConnectionPool.newConnection(DBConnetionPool.java:186)
at org.serviio.db.DBConnectionPool.getConnection(DBConnetionPool.java:123)
at org.serviio.db.DBConnectionPool.getConnection(DBConnetionPool.java:149)
at org.serviio.db.DatabaseManager.getConnection(DatabaseManager.java:71)
at org.serviio.db.DatabaseManager.getConnection(DatabaseManager.java:64)
at org.serviio.update.dao.DBLogDAOImpl.isScriptPresent(DBLogDAOImpl.java:49)
at org.serviio.update.DBSchemaUpdateExecutor.updateDBSchema(DBSchemaUpdateExecutor.java:77)
at org.serviio.MediaServer.main(MediaServer.java:121)
Caused by: ERROR XJ041: Failed to create database 'db', see the next exception for details.
at org.apache.derby.iapi.error.StandardException.newException(Unknown Source)
at org.apache.derby.impl.jdbc.SQLExceptionFactory.wrapArgsForTransportAcrossDRDA(Unknown Source)
... 19 more
Caused by: ERROR XBM0A: The database directory '/Library/Application Support/Serviio/library/db' exists. However, it does not contain the expected 'service.properties' file. Perhaps Derby was brought down in the middle of creating this database. You may want to delete this directory and try creating the database again.
at org.apache.derby.iapi.error.StandardException.newException(Unknown Source)
at org.apache.derby.iapi.error.StandardException.newException(Unknown Source)
at org.apache.derby.impl.services.monitor.StorageFactoryService.vetService(Unknown Source)
at org.apache.derby.impl.services.monitor.StorageFactoryService.access$900(Unknown Source)
at org.apache.derby.impl.services.monitor.StorageFactoryService$10.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at org.apache.derby.impl.services.monitor.StorageFactoryService.createServiceRoot(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.bootService(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.createPersistentService(Unknown Source)
at org.apache.derby.impl.services.monitor.FileMonitor.createPersistentService(Unknown Source)
at org.apache.derby.iapi.services.monitor.Monitor.createPersistentService(Unknown Source)
... 16 more
2016-01-02 21:22:16,430 ERROR [MediaServer] An unexpected error occured. Ending the application. Message: null
java.lang.NullPointerException
at org.serviio.update.dao.DBLogDAOImpl.isScriptPresent(DBLogDAOImpl.java:50)
at org.serviio.update.DBSchemaUpdateExecutor.updateDBSchema(DBSchemaUpdateExecutor.java:77)
at org.serviio.MediaServer.main(MediaServer.java:121)