diff --git a/app/__init__.py b/app/__init__.py
index 11d728a3..65707c26 100644
--- a/app/__init__.py
+++ b/app/__init__.py
@@ -25,7 +25,12 @@ from flask_moment import Moment
 from flask_caching import Cache
 import sqlalchemy
 
-from app.scodoc.sco_exceptions import ScoGenError, ScoValueError, APIInvalidParams
+from app.scodoc.sco_exceptions import (
+    AccessDenied,
+    ScoGenError,
+    ScoValueError,
+    APIInvalidParams,
+)
 from config import DevConfig
 import sco_version
 
@@ -51,6 +56,10 @@ def handle_sco_value_error(exc):
     return render_template("sco_value_error.html", exc=exc), 404
 
 
+def handle_access_denied(exc):
+    return render_template("error_access_denied.html", exc=exc), 403
+
+
 def internal_server_error(e):
     """Bugs scodoc, erreurs 500"""
     # note that we set the 500 status explicitly
@@ -181,6 +190,7 @@ def create_app(config_class=DevConfig):
 
     app.register_error_handler(ScoGenError, handle_sco_value_error)
     app.register_error_handler(ScoValueError, handle_sco_value_error)
+    app.register_error_handler(AccessDenied, handle_access_denied)
     app.register_error_handler(500, internal_server_error)
     app.register_error_handler(503, postgresql_server_error)
     app.register_error_handler(APIInvalidParams, handle_invalid_usage)
diff --git a/app/scodoc/sco_exceptions.py b/app/scodoc/sco_exceptions.py
index ec487b09..1ae86e65 100644
--- a/app/scodoc/sco_exceptions.py
+++ b/app/scodoc/sco_exceptions.py
@@ -45,10 +45,6 @@ class InvalidEtudId(NoteProcessError):
     pass
 
 
-class AccessDenied(ScoException):
-    pass
-
-
 class InvalidNoteValue(ScoException):
     pass
 
@@ -92,6 +88,10 @@ class ScoGenError(ScoException):
         ScoException.__init__(self, msg)
 
 
+class AccessDenied(ScoGenError):
+    pass
+
+
 class ScoInvalidDateError(ScoValueError):
     pass
 
diff --git a/app/scodoc/sco_import_users.py b/app/scodoc/sco_import_users.py
index 89ac9989..cb98ddbe 100644
--- a/app/scodoc/sco_import_users.py
+++ b/app/scodoc/sco_import_users.py
@@ -109,8 +109,11 @@ def import_excel_file(datafile):
     if not exceldata:
         raise ScoValueError("Ficher excel vide ou invalide")
     _, data = sco_excel.excel_bytes_to_list(exceldata)
-    if not data:  # probably a bug
-        raise ScoException("import_excel_file: empty file !")
+    if not data:
+        raise ScoValueError(
+            """Le fichier xlsx attendu semble vide !
+            """
+        )
     # 1-  --- check title line
     fs = [scu.stripquotes(s).lower() for s in data[0]]
     log("excel: fs='%s'\ndata=%s" % (str(fs), str(data)))
diff --git a/app/views/scodoc.py b/app/views/scodoc.py
index aad2e919..2ccac928 100644
--- a/app/views/scodoc.py
+++ b/app/views/scodoc.py
@@ -61,6 +61,7 @@ from app.decorators import (
     scodoc,
     permission_required_compat_scodoc7,
 )
+from app.scodoc.sco_exceptions import AccessDenied
 from app.scodoc.sco_permissions import Permission
 from app.views import scodoc_bp as bp
 
diff --git a/sco_version.py b/sco_version.py
index 714ef9fd..1505aa7a 100644
--- a/sco_version.py
+++ b/sco_version.py
@@ -1,7 +1,7 @@
 # -*- mode: python -*-
 # -*- coding: utf-8 -*-
 
-SCOVERSION = "9.0.51"
+SCOVERSION = "9.0.52"
 
 SCONAME = "ScoDoc"