diff --git a/app/scodoc/notesdb.py b/app/scodoc/notesdb.py
index 76792126..8226c1e2 100644
--- a/app/scodoc/notesdb.py
+++ b/app/scodoc/notesdb.py
@@ -117,6 +117,9 @@ def DBInsertDict(cnx, table, vals, commit=0, convert_empty_to_nulls=1):
     return oid
 
 
+_SQL_REMOVE_BAD_CHARS = str.maketrans("", "", '%*()+=&|[]"`')
+
+
 def DBSelectArgs(
     cnx,
     table,
@@ -168,7 +171,7 @@ def DBSelectArgs(
     #  n'autorise pas d'expressions
     if test == "~":
         for k in vals.keys():
-            vals[k] = vals[k].translate(string.maketrans("", ""), '%*()+=&|[]"`')
+            vals[k] = vals[k].translate(_SQL_REMOVE_BAD_CHARS)
 
     if vals:
         if aux_tables:  # paren
diff --git a/app/scodoc/sco_entreprises.py b/app/scodoc/sco_entreprises.py
index 00c19a4f..8fb076a7 100644
--- a/app/scodoc/sco_entreprises.py
+++ b/app/scodoc/sco_entreprises.py
@@ -290,7 +290,7 @@ def do_entreprise_check_etudiant(context, etudiant):
     Sinon, retourne (0, 'message explicatif')
     """
     etudiant = etudiant.strip().translate(
-        None, "'()"
+        str.maketrans("", "", "'()")
     )  # suppress parens and quote from name
     if not etudiant:
         return 1, None
diff --git a/app/scodoc/sco_formsemestre_edit.py b/app/scodoc/sco_formsemestre_edit.py
index a35b1631..d4e2b65f 100644
--- a/app/scodoc/sco_formsemestre_edit.py
+++ b/app/scodoc/sco_formsemestre_edit.py
@@ -1093,8 +1093,11 @@ def do_formsemestre_clone(
                 pvalue = prefs[pname]
                 try:
                     prefs.base_prefs.set(formsemestre_id, pname, pvalue)
-                except:
-                    log("do_formsemestre_clone: ignoring old preference %s" % pname)
+                except ValueError:
+                    log(
+                        "do_formsemestre_clone: ignoring old preference %s=%s for %s"
+                        % (pname, pvalue, formsemestre_id)
+                    )
 
     # 5- Copy formules utilisateur
     objs = sco_compute_moy.formsemestre_ue_computation_expr_list(
diff --git a/app/scodoc/sco_groups_view.py b/app/scodoc/sco_groups_view.py
index 3c218fb1..08c4c527 100644
--- a/app/scodoc/sco_groups_view.py
+++ b/app/scodoc/sco_groups_view.py
@@ -405,7 +405,7 @@ class DisplayedGroupsInfos(object):
             self.groups_titles = ", ".join(groups_titles)
             self.groups_filename = "_".join(groups_titles).replace(" ", "_")
             # Sanitize filename:
-            self.groups_filename = self.groups_filename.translate(None, ":/\\")
+            self.groups_filename = scu.make_filename(self.groups_filename)
 
         # colonnes pour affichages nom des groupes:
         # gère le cas où les étudiants appartiennent à des semestres différents
diff --git a/app/scodoc/sco_utils.py b/app/scodoc/sco_utils.py
index 637bbf75..819a37e9 100644
--- a/app/scodoc/sco_utils.py
+++ b/app/scodoc/sco_utils.py
@@ -480,16 +480,19 @@ def sanitize_string(s):
 
     For ids and some filenames
     """
-    return (
-        suppress_accents(s.translate(None, "'`\"<>!&\\ "))
-        .replace(" ", "_")
-        .replace("\t", "_")
-    )
+    # Table suppressing some chars:
+    trans = str.maketrans("", "", "'`\"<>!&\\ ")
+    return suppress_accents(s.translate(trans)).replace(" ", "_").replace("\t", "_")
+
+
+_BAD_FILENAME_CHARS = str.maketrans("", "", ":/\\")
 
 
 def make_filename(name):
-    """Try to convert name to a reasonnable filename"""
-    return suppress_accents(name).replace(" ", "_")
+    """Try to convert name to a reasonable filename
+    without spaces, (back)slashes, : and without accents
+    """
+    return suppress_accents(name.translate(_BAD_FILENAME_CHARS)).replace(" ", "_")
 
 
 VALID_CARS = (
diff --git a/misc/extract_code_strings.py b/misc/extract_code_strings.py
index ad16304d..651900d7 100755
--- a/misc/extract_code_strings.py
+++ b/misc/extract_code_strings.py
@@ -31,7 +31,7 @@ for srcfilename in sys.argv[1:]:
                 else:
                     s = x.s.encode("UTF-8")
                 # remove tabs and cr
-                s = s.translate(None, "\t\n")
+                s = s.replace("\t", "").replace("\n", "")
                 if len(s):
                     print("%s\t%s" % (srcfilename, s))