diff --git a/check_process b/check_process
index 38b168a..e41f11a 100644
--- a/check_process
+++ b/check_process
@@ -4,7 +4,7 @@
 ;; Default test serie
 	; pre-install
 		sudo yunohost tools update apps
-		sudo yunohost app install https://github.com/YunoHost-Apps/synapse_ynh/ -a "domain=$domain&server_name=$server_name&is_public=$is_public&jitsi_server=$jitsi_server" --force
+		sudo yunohost app info synapse --quiet > /dev/null || sudo yunohost app install https://github.com/YunoHost-Apps/synapse_ynh/ -a "domain=$domain&server_name=$server_name&is_public=$is_public&jitsi_server=$jitsi_server" --force
 	; Manifest
 		port="8449"	(PORT)
 		synapsenumber="1"