diff --git a/app/scodoc/sco_abs.py b/app/scodoc/sco_abs.py
index 2ae03ce81..77cc6048d 100644
--- a/app/scodoc/sco_abs.py
+++ b/app/scodoc/sco_abs.py
@@ -229,8 +229,11 @@ def DateRangeISO(date_beg, date_end, workable=1):
         date_end = date_beg
     r = []
     work_saturday = is_work_saturday()
-    cur = ddmmyyyy(date_beg, work_saturday=work_saturday)
-    end = ddmmyyyy(date_end, work_saturday=work_saturday)
+    try:
+        cur = ddmmyyyy(date_beg, work_saturday=work_saturday)
+        end = ddmmyyyy(date_end, work_saturday=work_saturday)
+    except (AttributeError, ValueError) as e:
+        raise ScoValueError("date invalide !") from e
     while cur <= end:
         if (not workable) or cur.iswork():
             r.append(cur)