diff --git a/Modules/IGT/IO/mitkNavigationDataSequentialPlayer.cpp b/Modules/IGT/IO/mitkNavigationDataSequentialPlayer.cpp
index ee84291442..28708d0e48 100644
--- a/Modules/IGT/IO/mitkNavigationDataSequentialPlayer.cpp
+++ b/Modules/IGT/IO/mitkNavigationDataSequentialPlayer.cpp
@@ -1,94 +1,97 @@
 /*===================================================================
 
 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 "mitkNavigationDataSequentialPlayer.h"
 
 #include <itksys/SystemTools.hxx> //for the pause
 #include <fstream>
 #include <sstream>
 
 //Exceptions
 #include "mitkIGTException.h"
 #include "mitkIGTIOException.h"
 
 mitk::NavigationDataSequentialPlayer::NavigationDataSequentialPlayer()
   : m_Repeat(false)
 {
 }
 
 mitk::NavigationDataSequentialPlayer::~NavigationDataSequentialPlayer()
 {
 }
 
 void mitk::NavigationDataSequentialPlayer::GoToSnapshot(unsigned int i)
 {
   if( !m_Repeat && (this->GetNumberOfSnapshots() <= i) )
   {
     MITK_ERROR << "Snaphot " << i << " does not exist and repat is off: can't go to that snapshot!";
     mitkThrowException(mitk::IGTException) << "Snapshot " << i << " does not exist and repat is off: can't go to that snapshot!";
   }
 
   // set iterator to given position (modulo for allowing repeat)
   m_NavigationDataSetIterator = m_NavigationDataSet->Begin() + ( i % this->GetNumberOfSnapshots() );
 
   // set outputs to selected snapshot
   this->GoToNextSnapshot();
 }
 
 bool mitk::NavigationDataSequentialPlayer::GoToNextSnapshot()
 {
+  if (m_NavigationDataSetIterator == m_NavigationDataSet->End())
+  {
+    MITK_WARN("NavigationDataSequentialPlayer") << "Cannot go to next snapshot, already at end of NavigationDataset. Ignoring...";
+    return false;
+  }
+  ++m_NavigationDataSetIterator;
   if ( m_NavigationDataSetIterator == m_NavigationDataSet->End() )
   {
     if ( m_Repeat )
     {
       // set data back to start if repeat is enabled
       m_NavigationDataSetIterator = m_NavigationDataSet->Begin();
     }
     else
     {
       return false;
     }
   }
-
-  ++m_NavigationDataSetIterator;
-
   return true;
 }
 
 void mitk::NavigationDataSequentialPlayer::GenerateData()
 {
   if ( m_NavigationDataSetIterator == m_NavigationDataSet->End() )
   {
     // no more data available
     this->GraftEmptyOutput();
   }
   else
   {
     for (unsigned int index = 0; index < GetNumberOfOutputs(); index++)
     {
       mitk::NavigationData* output = this->GetOutput(index);
       if( !output ) { mitkThrowException(mitk::IGTException) << "Output of index "<<index<<" is null."; }
 
       output->Graft(m_NavigationDataSetIterator->at(index));
     }
   }
 }
 
 void mitk::NavigationDataSequentialPlayer::UpdateOutputInformation()
 {
   this->Modified();  // make sure that we need to be updated
   Superclass::UpdateOutputInformation();
 }
\ No newline at end of file