diff --git a/scripts/install b/scripts/install
index 9cc73ea..7a461a0 100755
--- a/scripts/install
+++ b/scripts/install
@@ -52,6 +52,9 @@ ynh_script_progression --message="Validating installation parameters..." --weigh
 ### If the app uses NGINX as web server (written in HTML/PHP in most cases), the final path should be "/var/www/$app".
 ### If the app provides an internal web server (or uses another application server such as uWSGI), the final path should be "/opt/yunohost/$app"
 final_path=/var/www/$YNH_APP_ARG_APP_ID/icecoder
+
+test -e "/var/www/$YNH_APP_ARG_APP_ID/icecoder" || ynh_die --message="You have already installed a app instance here before installing this app instance!"
+test -e "/var/www/$YNH_APP_ARG_APP_ID" || ynh_die --message="You don't have installed a webapp before installing this app!"
 test ! -e "$final_path" || ynh_die --message="This path already contains a folder"
 
 # Register (book) web path