diff --git a/scripts/upgrade b/scripts/upgrade
index 3a95b29..e44d0a2 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -11,6 +11,13 @@ app=bozon
 path=$(sudo yunohost app setting $app path)
 stable=$(sudo yunohost app setting $app version)
 is_public=$(sudo yunohost app setting $app is_public)
+filesize=$(sudo yunohost app setting $app filesize)
+if [ "${#filesize}" -eq 0 ]
+then	# in old script filesize was not saved as an setting
+    domain=$(sudo yunohost app setting $app domain)
+	filesize=$(cat /etc/nginx/conf.d/$domain.d/$app.conf | grep -Po 'client_max_body_size \K.*(?=;)')
+	sudo yunohost app setting $app filesize -v "$filesize"
+fi
 
 # definie useful vars
 parent_path=/var/www