diff --git a/app/scodoc/sco_dump_db.py b/app/scodoc/sco_dump_db.py
index b11f63ca8..f9521b292 100644
--- a/app/scodoc/sco_dump_db.py
+++ b/app/scodoc/sco_dump_db.py
@@ -186,18 +186,28 @@ def _send_db(ano_db_name):
 
     log("uploading anonymized dump...")
     files = {"file": (ano_db_name + ".dump", dump)}
-    r = requests.post(
-        scu.SCO_DUMP_UP_URL,
-        files=files,
-        data={
-            "dept_name": sco_preferences.get_preference("DeptName"),
-            "serial": _get_scodoc_serial(),
-            "sco_user": str(current_user),
-            "sent_by": sco_users.user_info(str(current_user))["nomcomplet"],
-            "sco_version": sco_version.SCOVERSION,
-            "sco_fullversion": scu.get_scodoc_version(),
-        },
-    )
+    try:
+        r = requests.post(
+            scu.SCO_DUMP_UP_URL,
+            files=files,
+            data={
+                "dept_name": sco_preferences.get_preference("DeptName"),
+                "serial": _get_scodoc_serial(),
+                "sco_user": str(current_user),
+                "sent_by": sco_users.user_info(str(current_user))["nomcomplet"],
+                "sco_version": sco_version.SCOVERSION,
+                "sco_fullversion": scu.get_scodoc_version(),
+            },
+        )
+    except requests.exceptions.ConnectionError as exc:
+        raise ScoValueError(
+            """
+        Impossible de joindre le serveur d'assistance (scodoc.org).
+        Veuillez contacter le service informatique de votre établissement pour
+        corriger la configuration de ScoDoc. Dans la plupart des cas, il
+        s'agit d'un proxy mal configuré.
+        """
+        ) from exc
     return r