diff --git a/Modules/IGTUI/Qmitk/QmitkNavigationDataSourceSelectionWidget.cpp b/Modules/IGTUI/Qmitk/QmitkNavigationDataSourceSelectionWidget.cpp
index 95bddf2e38..3318ee5285 100644
--- a/Modules/IGTUI/Qmitk/QmitkNavigationDataSourceSelectionWidget.cpp
+++ b/Modules/IGTUI/Qmitk/QmitkNavigationDataSourceSelectionWidget.cpp
@@ -1,118 +1,126 @@
 /*===================================================================
 
 The Medical Imaging Interaction Toolkit (MITK)
 
 Copyright (c) German Cancer Research Center,
 Division of Medical and Biological Informatics.
 All rights reserved.
 
 This software is distributed WITHOUT ANY WARRANTY; without
 even the implied warranty of MERCHANTABILITY or FITNESS FOR
 A PARTICULAR PURPOSE.
 
 See LICENSE.txt or http://www.mitk.org for details.
 
 ===================================================================*/
 
 #include "QmitkNavigationDataSourceSelectionWidget.h"
 
 //mitk headers
 #include <mitkNavigationDataSource.h>
 #include <mitkGetModuleContext.h>
 #include <qlistwidget.h>
 
 
 
 
 QmitkNavigationDataSourceSelectionWidget::QmitkNavigationDataSourceSelectionWidget(QWidget* parent, Qt::WindowFlags f)
 : QWidget(parent, f)
 {
   m_Controls = NULL;
   CreateQtPartControl(this);
   CreateConnections();
 
 }
 
 
 QmitkNavigationDataSourceSelectionWidget::~QmitkNavigationDataSourceSelectionWidget()
 {
 
 }
 
 void QmitkNavigationDataSourceSelectionWidget::CreateQtPartControl(QWidget *parent)
 {
   if (!m_Controls)
   {
     // create GUI widgets
     m_Controls = new Ui::QmitkNavigationDataSourceSelectionWidgetControls;
     m_Controls->setupUi(parent);
 
     std::string empty = "";
     m_Controls->m_NaviagationDataSourceWidget->Initialize<mitk::NavigationDataSource>(mitk::NavigationDataSource::US_PROPKEY_DEVICENAME,empty);
 
   }
 }
 
 void QmitkNavigationDataSourceSelectionWidget::CreateConnections()
 {
   if ( m_Controls )
   {
     connect( (QObject*)(m_Controls->m_NaviagationDataSourceWidget), SIGNAL(ServiceSelectionChanged(mitk::ServiceReference*)), this, SLOT(NavigationDataSourceSelected(mitk::ServiceReference*)) );
 
   }
 }
 
 void QmitkNavigationDataSourceSelectionWidget::NavigationDataSourceSelected(mitk::ServiceReference* s)
   {
+    if (s==NULL) //no device selected
+      {
+        //reset everything
+        m_CurrentSource = NULL;
+        m_CurrentStorage = NULL;
+        return;
+      }
+
     // Get Source
     m_CurrentSource = this->m_Controls->m_NaviagationDataSourceWidget->TranslateReference<mitk::NavigationDataSource>(*s);
     std::string id = s->GetProperty(mitk::NavigationDataSource::US_PROPKEY_ID).ToString();
     mitk::ModuleContext* context = mitk::GetModuleContext();
     
     //Fill tool list
     for(int i = 0; i < m_CurrentSource->GetNumberOfOutputs(); i++) {new QListWidgetItem(tr(m_CurrentSource->GetOutput(i)->GetName()), m_Controls->m_ToolView);}
     
         
     // Create Filter for ToolStorage
     std::string filter = "(&(" + mitk::ServiceConstants::OBJECTCLASS() + "=" + mitk::NavigationToolStorage::US_INTERFACE_NAME + ")("+ mitk::NavigationToolStorage::US_PROPKEY_SOURCE_ID + "=" + id + "))";
         
     // Get Storage 
     std::list<mitk::ServiceReference> refs = context->GetServiceReferences(mitk::NavigationToolStorage::US_INTERFACE_NAME, filter);
     if (refs.size() == 0) return; //no storage was found
     m_CurrentStorage = context->GetService<mitk::NavigationToolStorage>(refs.front());
     if (m_CurrentStorage.IsNull())
       {
       MITK_WARN << "Found an invalid storage object!";
       return;
       }
     if (m_CurrentStorage->GetToolCount() != m_CurrentSource->GetNumberOfOutputs()) //there is something wrong with the storage
       {
       MITK_WARN << "Found a tool storage, but it has not the same number of tools like the NavigationDataSource. This storage won't be used because it isn't the right one.";
       m_CurrentStorage = NULL;
       }    
   }
 
 mitk::NavigationDataSource::Pointer QmitkNavigationDataSourceSelectionWidget::GetSelectedNavigationDataSource()
   {
   return this->m_CurrentSource;
   }
 
 
 int QmitkNavigationDataSourceSelectionWidget::GetSelectedToolID()
   {
     return this->m_Controls->m_ToolView->currentIndex().row();
   }
 
 
 mitk::NavigationTool::Pointer QmitkNavigationDataSourceSelectionWidget::GetSelectedNavigationTool()
   {
     if (this->m_CurrentStorage.IsNull()) return NULL;
     if (m_Controls->m_ToolView->currentIndex().row() >= m_CurrentStorage->GetToolCount()) return NULL;
     return this->m_CurrentStorage->GetTool(m_Controls->m_ToolView->currentIndex().row());
   }
 
 
 mitk::NavigationToolStorage::Pointer QmitkNavigationDataSourceSelectionWidget::GetNavigationToolStorageOfSource()
   {
     return this->m_CurrentStorage;
   }
\ No newline at end of file