diff --git a/src/python/dm/__init__.py b/src/python/dm/__init__.py
index 0f79051400fec8637fcd97e5b7930a1b6e33754f..449f9b89c20c1ac73ca48b17af3b615a53db29e6 100644
--- a/src/python/dm/__init__.py
+++ b/src/python/dm/__init__.py
@@ -1 +1 @@
-__version__ = "0.2 (2015.07.07)"
+__version__ = "0.5 (2015.11.06)"
diff --git a/src/python/dm/ds_web_service/service/impl/experimentSessionControllerImpl.py b/src/python/dm/ds_web_service/service/impl/experimentSessionControllerImpl.py
index 7958faa7493b4c9d37b86520ddd220428bcd6291..05af7916b994e7192afd89fa2551ed05103f73b2 100755
--- a/src/python/dm/ds_web_service/service/impl/experimentSessionControllerImpl.py
+++ b/src/python/dm/ds_web_service/service/impl/experimentSessionControllerImpl.py
@@ -51,9 +51,8 @@ class ExperimentSessionControllerImpl(DmObjectManager):
 
     def updateExperiment(self, name):
         experiment = self.experimentDbApi.getExperimentWithUsers(name)
-        if experiment.get('startDate') is None:
-            raise InvalidRequest('Experiment %s has not been started.' % name)
-        ExperimentManager.getInstance().updateExperimentGroupUsers(experiment)
+        if experiment.get('startDate') is not None:
+            ExperimentManager.getInstance().updateExperimentGroupUsers(experiment)
         return experiment
 
     def stopExperiment(self, name):