diff --git a/Modules/IGT/IGTFilters/mitkTrackingDeviceSourceConfigurator.cpp b/Modules/IGT/IGTFilters/mitkTrackingDeviceSourceConfigurator.cpp
index 09a95e7426..bf43af8333 100644
--- a/Modules/IGT/IGTFilters/mitkTrackingDeviceSourceConfigurator.cpp
+++ b/Modules/IGT/IGTFilters/mitkTrackingDeviceSourceConfigurator.cpp
@@ -1,247 +1,250 @@
 /*=========================================================================
 
 Program:   Medical Imaging & Interaction Toolkit
 Language:  C++
 Date:      $Date: 2011-01-18 13:22:38 +0100 (Di, 18 Jan 2011) $
 Version:   $Revision: 28959 $
 
 Copyright (c) German Cancer Research Center, Division of Medical and
 Biological Informatics. All rights reserved.
 See MITKCopyright.txt or http://www.mitk.org/copyright.html for details.
 
 This software is distributed WITHOUT ANY WARRANTY; without even
 the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 PURPOSE.  See the above copyright notices for more information.
 
 =========================================================================*/
 
 #include "mitkTrackingDeviceSourceConfigurator.h"
 
 #include "mitkNDITrackingDevice.h"
 #include "mitkClaronTrackingDevice.h"
 
 
 mitk::TrackingDeviceSourceConfigurator::TrackingDeviceSourceConfigurator(mitk::NavigationToolStorage::Pointer NavigationTools, mitk::TrackingDevice::Pointer TrackingDevice)
 {
 //make a copy of the navigation tool storage because we will modify the storage
-m_NavigationTools = mitk::NavigationToolStorage::New();
-for (int i=0; i<NavigationTools->GetToolCount(); i++)
+if (NavigationTools.IsNotNull())
+  {
+  m_NavigationTools = mitk::NavigationToolStorage::New();
+  for (int i=0; i<NavigationTools->GetToolCount(); i++)
       {
       m_NavigationTools->AddTool(NavigationTools->GetTool(i));   
       }
+  }
 
 m_TrackingDevice = TrackingDevice;
 m_ToolCorrespondencesInToolStorage = std::vector<int>();
 m_ErrorMessage = "";
 }
 
 mitk::NavigationToolStorage::Pointer mitk::TrackingDeviceSourceConfigurator::GetUpdatedNavigationToolStorage()
 {
 return m_NavigationTools;
 }
 
 
 mitk::TrackingDeviceSourceConfigurator::~TrackingDeviceSourceConfigurator()
 {
 }
 
 bool mitk::TrackingDeviceSourceConfigurator::IsCreateTrackingDeviceSourcePossible()
 {
 if (m_NavigationTools.IsNull())
   {
   m_ErrorMessage = "NavigationToolStorage is NULL!";
   return false;
   }
 else if (m_TrackingDevice.IsNull())
   {
   m_ErrorMessage = "TrackingDevice is NULL!";
   return false;
   }
 else
   {
   for (int i=0; i<m_NavigationTools->GetToolCount(); i++)
     {
     if (m_NavigationTools->GetTool(i)->GetTrackingDeviceType() != m_TrackingDevice->GetType()) 
       {
       m_ErrorMessage = "At least one tool is not of the same type like the tracking device.";
       return false;
       }
     }
   //TODO in case of Aurora: check if the tools are automatically detected by comparing the serial number
   return true;
   }
 }
 
 mitk::TrackingDeviceSource::Pointer mitk::TrackingDeviceSourceConfigurator::CreateTrackingDeviceSource()
 {
 mitk::NavigationDataObjectVisualizationFilter::Pointer dummy;
 return this->CreateTrackingDeviceSource(dummy); 
 }
 
 mitk::TrackingDeviceSource::Pointer mitk::TrackingDeviceSourceConfigurator::CreateTrackingDeviceSource(mitk::NavigationDataObjectVisualizationFilter::Pointer &visualizationFilter)
 {
   if (!this->IsCreateTrackingDeviceSourcePossible()) return NULL;
   mitk::TrackingDeviceSource::Pointer returnValue;
   
   //create tracking device source
   if (m_TrackingDevice->GetType()==mitk::NDIAurora) {returnValue = CreateNDIAuroraTrackingDeviceSource(m_TrackingDevice,m_NavigationTools);}
   else if (m_TrackingDevice->GetType()==mitk::NDIPolaris) {returnValue = CreateNDIPolarisTrackingDeviceSource(m_TrackingDevice,m_NavigationTools);}
   else if (m_TrackingDevice->GetType()==mitk::ClaronMicron) {returnValue = CreateMicronTrackerTrackingDeviceSource(m_TrackingDevice,m_NavigationTools);}
     //TODO: insert other tracking systems? 
   if (returnValue.IsNull()) return NULL;
 
   //create visualization filter
   visualizationFilter = CreateNavigationDataObjectVisualizationFilter(returnValue,m_NavigationTools);
   if (visualizationFilter.IsNull()) return NULL;
   
   return returnValue;
 }
     
 std::string mitk::TrackingDeviceSourceConfigurator::GetErrorMessage()
 {
   return this->m_ErrorMessage;
 }
 
 //############################ internal help methods ########################################
 
 mitk::TrackingDeviceSource::Pointer mitk::TrackingDeviceSourceConfigurator::CreateNDIPolarisTrackingDeviceSource(mitk::TrackingDevice::Pointer trackingDevice, mitk::NavigationToolStorage::Pointer navigationTools)
   {
   mitk::TrackingDeviceSource::Pointer returnValue = mitk::TrackingDeviceSource::New();
   mitk::NDITrackingDevice::Pointer thisDevice = dynamic_cast<mitk::NDITrackingDevice*>(trackingDevice.GetPointer());
   m_ToolCorrespondencesInToolStorage = std::vector<int>();
   //add the tools to the tracking device
   for (int i=0; i<navigationTools->GetToolCount(); i++)
       {
         mitk::NavigationTool::Pointer thisNavigationTool = m_NavigationTools->GetTool(i);
         m_ToolCorrespondencesInToolStorage.push_back(i);
         bool toolAddSuccess = thisDevice->AddTool(thisNavigationTool->GetToolName().c_str(),thisNavigationTool->GetCalibrationFile().c_str());
         if (!toolAddSuccess)
           {
           this->m_ErrorMessage = "Can't add tool, is the SROM-file valid?";
           return NULL;
           }
       } 
   returnValue->SetTrackingDevice(thisDevice);
   return returnValue;
   }
 
 mitk::TrackingDeviceSource::Pointer mitk::TrackingDeviceSourceConfigurator::CreateNDIAuroraTrackingDeviceSource(mitk::TrackingDevice::Pointer trackingDevice, mitk::NavigationToolStorage::Pointer navigationTools)
   {
   mitk::TrackingDeviceSource::Pointer returnValue = mitk::TrackingDeviceSource::New();
   mitk::NDITrackingDevice::Pointer thisDevice = dynamic_cast<mitk::NDITrackingDevice*>(trackingDevice.GetPointer());
 
   //connect to aurora to dectect tools automatically
   thisDevice->OpenConnection();
   thisDevice->StartTracking();
   
   //now search for automatically detected tools in the tool storage and save them
   mitk::NavigationToolStorage::Pointer newToolStorageInRightOrder = mitk::NavigationToolStorage::New();
   std::vector<int> alreadyFoundTools = std::vector<int>();
   m_ToolCorrespondencesInToolStorage = std::vector<int>();
   for (int i=0; i<thisDevice->GetToolCount(); i++)
       {
       bool toolFound = false;
       for (int j=0; j<navigationTools->GetToolCount(); j++)
         {
           //check if the serial number is the same to identify the tool
           if ((dynamic_cast<mitk::NDIPassiveTool*>(thisDevice->GetTool(i)))->GetSerialNumber() == navigationTools->GetTool(j)->GetSerialNumber())
             {
             //check if this tool was already added to make sure that every tool is only added once (in case of same serial numbers)
             bool toolAlreadyAdded = false;
             for(int k=0; k<alreadyFoundTools.size(); k++) if (alreadyFoundTools.at(k) == j) toolAlreadyAdded = true;
             
             if(!toolAlreadyAdded)
               {
               //add tool in right order
               newToolStorageInRightOrder->AddTool(navigationTools->GetTool(j));
               //adapt name of tool
               dynamic_cast<mitk::NDIPassiveTool*>(thisDevice->GetTool(i))->SetToolName(navigationTools->GetTool(j)->GetToolName());
               //rember that this tool was already found
               alreadyFoundTools.push_back(j);
 
               toolFound = true;
               break;
               }
             }
         }
       if (!toolFound)
         {
         this->m_ErrorMessage = "Error: did not find every automatically detected tool in the loaded tool storage: aborting initialization.";
         return NULL;
         }
       }
   
   //delete all tools from the tool storage
   navigationTools->DeleteAllTools();
 
   //and add only the detected tools in the right order
   for (int i=0; i<newToolStorageInRightOrder->GetToolCount(); i++)
       {
       navigationTools->AddTool(newToolStorageInRightOrder->GetTool(i));   
       }
   returnValue->SetTrackingDevice(thisDevice);
   return returnValue;
   }
 
 mitk::TrackingDeviceSource::Pointer mitk::TrackingDeviceSourceConfigurator::CreateMicronTrackerTrackingDeviceSource(mitk::TrackingDevice::Pointer trackingDevice, mitk::NavigationToolStorage::Pointer navigationTools)  
   {
   mitk::TrackingDeviceSource::Pointer returnValue = mitk::TrackingDeviceSource::New();
   mitk::ClaronTrackingDevice::Pointer thisDevice = dynamic_cast<mitk::ClaronTrackingDevice*>(trackingDevice.GetPointer());
   m_ToolCorrespondencesInToolStorage = std::vector<int>();
   //add the tools to the tracking device
   for (int i=0; i<navigationTools->GetToolCount(); i++)
       {
         mitk::NavigationTool::Pointer thisNavigationTool = m_NavigationTools->GetTool(i);
         m_ToolCorrespondencesInToolStorage.push_back(i);
         bool toolAddSuccess = thisDevice->AddTool(thisNavigationTool->GetToolName().c_str(),thisNavigationTool->GetCalibrationFile().c_str());
         if (!toolAddSuccess)
           {
           this->m_ErrorMessage = "Can't add tool, is the toolfile valid?";
           return NULL;
           }
       } 
   returnValue->SetTrackingDevice(thisDevice);
   return returnValue;
   }
 
 mitk::NavigationDataObjectVisualizationFilter::Pointer mitk::TrackingDeviceSourceConfigurator::CreateNavigationDataObjectVisualizationFilter(mitk::TrackingDeviceSource::Pointer trackingDeviceSource, mitk::NavigationToolStorage::Pointer navigationTools)
   {
   mitk::NavigationDataObjectVisualizationFilter::Pointer returnValue = mitk::NavigationDataObjectVisualizationFilter::New();
   for (int i=0; i<trackingDeviceSource->GetNumberOfOutputs(); i++)
     {
     mitk::NavigationTool::Pointer currentTool = navigationTools->GetToolByName(trackingDeviceSource->GetOutput(i)->GetName());
     if (currentTool.IsNull())
       {
       this->m_ErrorMessage = "Error: did not find correspondig tool in tracking device after initialization.";
       return NULL;
       }
     returnValue->SetInput(i,trackingDeviceSource->GetOutput(i));
     returnValue->SetRepresentationObject(i,currentTool->GetDataNode()->GetData());
     }
   return returnValue;
   }
 
 int mitk::TrackingDeviceSourceConfigurator::GetToolNumberInToolStorage(int outputID)
   {
   if (outputID < m_ToolCorrespondencesInToolStorage.size()) return m_ToolCorrespondencesInToolStorage.at(outputID);
   else return -1;
   }
 
 std::string mitk::TrackingDeviceSourceConfigurator::GetToolIdentifierInToolStorage(int outputID)
   {
   if (outputID < m_ToolCorrespondencesInToolStorage.size()) return m_NavigationTools->GetTool(m_ToolCorrespondencesInToolStorage.at(outputID))->GetIdentifier();
   else return "";
   }
 
 std::vector<int> mitk::TrackingDeviceSourceConfigurator::GetToolNumbersInToolStorage()
   {
   return m_ToolCorrespondencesInToolStorage;
   }
 
 std::vector<std::string> mitk::TrackingDeviceSourceConfigurator::GetToolIdentifiersInToolStorage()
   {
   std::vector<std::string> returnValue = std::vector<std::string>();
   for (int i=0; i<m_ToolCorrespondencesInToolStorage.size(); i++)
     {returnValue.push_back(m_NavigationTools->GetTool(m_ToolCorrespondencesInToolStorage.at(i))->GetIdentifier());}
   return returnValue;
   }
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