diff --git a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/ETLService.java b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/ETLService.java
index 50dae27274a19471600a9fc03c7bc2496b9a610e..766ea0e3660c3179f87f9a659b494f25b40f6d3e 100644
--- a/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/ETLService.java
+++ b/openbis/source/java/ch/systemsx/cisd/openbis/generic/server/ETLService.java
@@ -365,8 +365,9 @@ public class ETLService extends AbstractCommonServer<IETLService> implements IET
     {
         assert sessionToken != null : "Unspecified session token.";
         assert samplePermID != null : "Unspecified sample perm ID.";
-        return daoFactory.getSampleDAO().tryToFindByPermID(samplePermID).getSampleIdentifier();
-        // FIXME null pointer exception
+
+        final SamplePE sample = daoFactory.getSampleDAO().tryToFindByPermID(samplePermID);
+        return (sample == null) ? null : sample.getSampleIdentifier();
     }
 
     private ExperimentPE tryLoadExperimentBySampleIdentifier(final Session session,
@@ -541,8 +542,6 @@ public class ETLService extends AbstractCommonServer<IETLService> implements IET
                 registerDataSet(sessionToken, experimentIdentifier, dataSet);
             }
         }
-        // TODO Auto-generated method stub
-
     }
 
     public long registerExperiment(String sessionToken, NewExperiment experiment)