diff --git a/scripts/upgrade b/scripts/upgrade
index b383b6b..c40a6c3 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -38,7 +38,7 @@ if [ -z "${smtp_host:-}" ]; then
 		smtp_password=$(ynh_read_var_in_file --file=$user_conf --key=SMTP_PASSWORD)
 		smtp_security=$(ynh_read_var_in_file --file=$user_conf --key=SMTP_SECURITY)
 		mail_return_path=$(ynh_read_var_in_file --file=$user_conf --key=MAIL_RETURN_PATH)
-		mail_sender=$(ynh_read_var_in_file --file=$user_conf --key=SMTP_SENDER)
+		mail_sender=$(ynh_read_var_in_file --file=$user_conf --key=MAIL_SENDER)
 		ynh_replace_string --match_string="const SMTP_" --replace_string="//const SMTP_" --target_file=$user_conf
 		ynh_replace_string --match_string="const MAIL_" --replace_string="//const MAIL_" --target_file=$user_conf
 	else