diff --git a/ArchiveExtractor.py b/ArchiveExtractor.py
index 195622551990edc2077ef939e4b7f19633a75161..f5bb8479bc14c5a3c84affabd4a42840e43ddfa5 100755
--- a/ArchiveExtractor.py
+++ b/ArchiveExtractor.py
@@ -127,12 +127,20 @@ def query_ADB_BetweenDates(attr,
         raise ValueError("Attribute '%s' is not archived in DB %s"%(attr, extractor))
 
     # Get its sampling period in seconds
-    samplingPeriod = int(ADB.GetArchivingMode(attr)[1])*10**-3
-    logger.debug("Attribute is sampled every %g seconds"%samplingPeriod)
+    try:
+        samplingPeriod = int(ADB.GetArchivingMode(attr)[1])*10**-3
+        logger.debug("Attribute is sampled every %g seconds"%samplingPeriod)
 
-    # Evaluate the number of points
-    est_N = (dateStop-dateStart).total_seconds()/samplingPeriod
-    logger.debug("Which leads to %d points to extract."%est_N)
+        # Evaluate the number of points
+        est_N = (dateStop-dateStart).total_seconds()/samplingPeriod
+        logger.debug("Which leads to %d points to extract."%est_N)
+
+    except ValueError:
+        logger.warning("Attribute has no sampling period. Maybe it's archived on event.")
+        logger.warning("Please note that this script does not cut acces into chunks for this type of attributes.")
+
+        # Temporary bypass estimation
+        est_N = 1
 
     # If data chunk is too much, we need to cut it
     if est_N > Nmax:
@@ -353,7 +361,8 @@ if __name__ == "__main__":
             # Add to result dictionnary
             results[attr] = datevalue
 
-        except ValueError:
+        except ValueError as e:
+            logger.debug("ErrorMsg: %s"%e)
             logger.warning("Failed to extract %s. Skipping..."%attr)
         except tango.CommunicationFailed:
             logger.warning("Failed to extract %s. Skipping..."%attr)