diff --git a/hal-default.db b/hal-default.db
index cd99a46d..7a7f4d09 100755
Binary files a/hal-default.db and b/hal-default.db differ
diff --git a/src/se/koc/hal/HalContext.java b/src/se/koc/hal/HalContext.java
index 1bd59bbe..25129a96 100755
--- a/src/se/koc/hal/HalContext.java
+++ b/src/se/koc/hal/HalContext.java
@@ -79,6 +79,7 @@ public class HalContext {
 
                 logger.fine(String.format("Upgrading DB (from: v%s, to: v%s)...", dbVersion, defaultDBVersion));
                 final DBUpgradeHandler handler = new DBUpgradeHandler(referenceDB);
+                handler.addIgnoredTable("db_version_history");
                 handler.setTargetDB(db);
                 
                 //read upgrade path preferences from the reference database
@@ -109,9 +110,6 @@ public class HalContext {
 				});
                 
                 handler.upgrade();
-                
-                //remove table from target database. this table is supposed to only be put in the reference db.
-                db.exec("DROP TABLE db_version_history");
 
                 logger.info("DB upgrade done");
                 dbConf.setProperty(PROPERTY_DB_VERSION, defaultDBConf.getProperty(PROPERTY_DB_VERSION));
diff --git a/src/se/koc/hal/PowerChallenge.java b/src/se/koc/hal/PowerChallenge.java
index 9baea619..e30c39af 100755
--- a/src/se/koc/hal/PowerChallenge.java
+++ b/src/se/koc/hal/PowerChallenge.java
@@ -27,11 +27,11 @@ import java.util.logging.Level;
  * Created by Ziver on 2015-12-03.
  */
 public class PowerChallenge {
-
 	
     private static HalDaemon[] daemons;
     private static HalHttpPage[] pages;
 
+
     public static void main(String[] args) throws Exception {
         // init logging
         CompactLogFormatter formatter = new CompactLogFormatter();
@@ -41,11 +41,12 @@ public class PowerChallenge {
         LogUtil.setFormatter("zutil", formatter);
         LogUtil.setGlobalFormatter(formatter);
 
+
         // init DB and other configurations
         HalContext.initialize();
         DBConnection db = HalContext.getDB();
 
-        // Init sensors and controllers
+        // Init sensors,events and controllers
         ControllerManager.initialize();
         for(Sensor sensor : Sensor.getLocalSensors(db)){
             ControllerManager.getInstance().register(sensor);
@@ -54,6 +55,7 @@ public class PowerChallenge {
             ControllerManager.getInstance().register(event);
         }
 
+
         // init daemons
         daemons = new HalDaemon[]{
                 new DataAggregatorDaemon(),
@@ -67,6 +69,8 @@ public class PowerChallenge {
             daemon.initiate(executor);
         }
 
+
+        // init http server
         pages = new HalHttpPage[]{
                 new PCOverviewHttpPage(),
                 new PCHeatMapHttpPage(),