diff --git a/Trigger/TriggerRelease/python/Modifiers.py b/Trigger/TriggerRelease/python/Modifiers.py
index 8269d22ae6fea7ed77613b38e2d72601abf1d582..0a9e9ec744969880edba51630cbe33577b2c1f26 100644
--- a/Trigger/TriggerRelease/python/Modifiers.py
+++ b/Trigger/TriggerRelease/python/Modifiers.py
@@ -354,7 +354,13 @@ class allowCOOLUpdates(_modifier):
     """
     def postSetup(self):
         if hasattr(svcMgr,'HltEventLoopMgr'):
-            svcMgr.HltEventLoopMgr.CoolUpdateTool.enable() 
+            svcMgr.HltEventLoopMgr.CoolUpdateTool.enable()
+            # Make sure relevant folders are marked as 'extensible'
+            for i, f in enumerate(svcMgr.IOVDbSvc.Folders):
+                if ('/Indet/Onl/Beampos' in f or '/TRIGGER/LUMI/HLTPrefLumi' in f) \
+                   and '<extensible/>' not in f:
+                    svcMgr.IOVDbSvc.Folders[i] += ' <extensible/>'
+                    log.info('IOVDbSvc folder %s not marked as extensible. Fixing this...', f)
 
 class useOracle(_modifier):
     """