diff --git a/scripts/upgrade b/scripts/upgrade
index 2398209..cb1008d 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -1,21 +1,59 @@
 #!/bin/bash
 
+# Source app helpers
+source /usr/share/yunohost/helpers
+
 # Retrieve arguments
 app=$YNH_APP_INSTANCE_NAME
-domain=$(sudo yunohost app setting $app domain)
+domain=$(ynh_app_setting_get $app domain)
 path="/Microsoft-Server-ActiveSync"
+final_path=$(ynh_app_setting_get $app final_path)
+final_logpath=$(ynh_app_setting_get $app final_logpath)
+final_nginxconf=$(ynh_app_setting_get $app final_nginxconf)
+final_phpconf=$(ynh_app_setting_get $app final_phpconf)
+
+# We make the app retro-compatible with previous versions
+if [ -z "$final_path" ];
+then
+   final_path="/var/www/$app"
+   ynh_app_setting_set "$app" final_path "$final_path"
+else
+   echo "${final_path} exists, we don't create it."
+fi
+
+if [ -z "$final_logpath" ];
+then
+   final_logpath="/var/log/$app"
+   ynh_app_setting_set "$app" final_logpath "$final_logpath"
+else
+   echo "${final_logpath} exists, we don't create it."
+fi
+
+if [ -z "$final_nginxconf" ];
+then
+   final_nginxconf="/etc/nginx/conf.d/${domain}.d/${app}.conf"
+   ynh_app_setting_set "$app" final_nginxconf "$final_nginxconf"
+else
+   echo "${final_nginxconf} exists, we don't create it."
+fi
+
+if [ -z "$final_phpconf" ];
+then
+   final_phpconf=/etc/php5/fpm/pool.d/$app.conf
+   ynh_app_setting_set "$app" final_phpconf "$final_phpconf"
+else
+   echo "${final_phpconf} exists, we don't create it."
+fi
+
 
 # Prereqs
 sudo apt-get install php-soap php5-imap libawl-php php5-xsl
 
 # Cleaning
-sudo rm -rf /var/www/$app
-sudo rm -rf /var/log/$app
-sudo rm -f /etc/nginx/conf.d/$domain.d/$app.conf
-sudo rm -f /etc/php5/fpm/pool.d/$app.conf
-
-final_logpath=/var/log/$app
-final_path=/var/www/$app
+sudo rm -rf $final_path
+sudo rm -rf $final_logpath
+sudo rm -f $final_nginxconf
+sudo rm -f $final_phpconf
 
 # Copy files to the right place
 sudo mkdir -p $final_path
@@ -55,7 +93,7 @@ else
 
         # Copy config
         sudo cp ../conf/config.php $final_path/config.php
-       sed -i "s@DOMAINTOCHANGE@$domain@g" ../conf/backend/config-imap.php
+        sed -i "s@DOMAINTOCHANGE@$domain@g" ../conf/backend/config-imap.php
         sed -i "s@FLAGTOCHANGE@false@g" ../conf/backend/config-imap.php
         sudo cp ../conf/backend/config-imap.php $final_path/backend/imap/config.php
 
@@ -64,7 +102,6 @@ fi
 # Set permissions to z-push directory
 sudo chown -R www-data: $final_path
 
-
 # Create log directory
 sudo mkdir -p $final_logpath
 sudo chmod 750 $final_logpath
@@ -76,18 +113,16 @@ sudo ln -s /usr/share/awl/inc/XML* /var/www/z-push/include/
 # Modify Nginx configuration file and copy it to Nginx conf directory
 sudo sed -i "s@ALIASTOCHANGE@$final_path/@g" ../conf/nginx.conf
 sudo sed -i "s@NAMETOCHANGE@$app@g" ../conf/nginx.conf
-sudo cp ../conf/nginx.conf /etc/nginx/conf.d/$domain.d/$app.conf
+sudo cp ../conf/nginx.conf $final_nginxconf
 
 # Dedicated php-fpm processes
 sudo sed -i "s@NAMETOCHANGE@$app@g" ../conf/php-fpm.conf
-finalphpconf=/etc/php5/fpm/pool.d/$app.conf
-sudo cp ../conf/php-fpm.conf $finalphpconf
-sudo chown root: $finalphpconf
-sudo chmod 644 $finalphpconf
-
-# Enable api for client
-sudo yunohost app setting $app skipped_uris -v "/"
+sudo cp ../conf/php-fpm.conf $final_phpconf
+sudo chown root: $final_phpconf
+sudo chmod 644 $final_phpconf
 
+# Enable api for client and make the app public
+ynh_app_setting_set $app skipped_uris "/"
 
 # Restart of services
 sudo service php5-fpm reload