diff --git a/scripts/upgrade b/scripts/upgrade
index e39d161..afdbfd9 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -52,6 +52,11 @@ upgrade_type=$(ynh_check_app_version_changed)
 #=================================================
 ynh_script_progression --message="Ensuring downward compatibility..." --weight=1
 
+if [ -z "$admin" ]; then
+	admin="default_value"
+	ynh_app_setting_set --app=$app --key=admin --value=$admin
+fi
+
 # Cleaning legacy permissions
 if ynh_legacy_permissions_exists; then
 	ynh_legacy_permissions_delete_all