diff --git a/scripts/_common.sh b/scripts/_common.sh
index 591ab81..64d54e9 100644
--- a/scripts/_common.sh
+++ b/scripts/_common.sh
@@ -26,8 +26,21 @@ mysql-to-pg() {
 		# Migrating from MySQL to PostgreSQL
 		pgloader mysql://mattermost:$mysql_db_pwd@localhost:3306/mattermost postgresql://mattermost:$db_pwd@localhost:5432/mattermost
 		
-		ynh_replace_string --match_string="\"DriverName\":*," --replace_string="\"DriverName\": \"postgres\"," --target_file="$final_path/config/config.json"
-		ynh_replace_string --match_string="\"DataSource\":*," --replace_string="\"DataSource\": \"postgres://$db_user:$db_pwd@localhost:5432/$db_name?sslmode=disable&connect_timeout=10\"," --target_file="$final_path/config/config.json"
+		#ynh_replace_string --match_string="\"DriverName\":*," --replace_string="\"DriverName\": \"postgres\"," --target_file="$final_path/config/config.json"
+		#ynh_replace_string --match_string="\"DataSource\":*," --replace_string="\"DataSource\": \"postgres://$db_user:$db_pwd@localhost:5432/$db_name?sslmode=disable&connect_timeout=10\"," --target_file="$final_path/config/config.json"
+
+		#=================================================
+		# MODIFY A CONFIG FILE
+		#=================================================
+		ynh_script_progression --message="Modifying a config file..." --weight=3
+
+		smtp_user_pwd=$(ynh_string_random --length=24)
+		url=https://$domain$path_url
+
+		ynh_add_config --template="../conf/config.json" --destination="$final_path/config/config.json"
+
+		chmod 400 "$final_path/config/config.json"
+		chown $app:$app "$final_path/config/config.json"
 
 		# Removinging MySQL database
 		ynh_mysql_remove_db --db_user=$db_user --db_name=$db_name
diff --git a/scripts/install b/scripts/install
index 5fdffd0..f9b5256 100644
--- a/scripts/install
+++ b/scripts/install
@@ -152,6 +152,9 @@ url=https://$domain$path_url
 
 ynh_add_config --template="../conf/config.json" --destination="$final_path/config/config.json"
 
+chmod 400 "$final_path/config/config.json"
+chown $app:$app "$final_path/config/config.json"
+
 #=================================================
 # NGINX CONFIGURATION
 #=================================================
diff --git a/scripts/upgrade b/scripts/upgrade
index 7c783d1..6b41429 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -177,6 +177,19 @@ ynh_exec_warn_less ynh_install_app_dependencies $pkg_dependencies
 # Migrating from MySQL to PostgreSQL
 mysql-to-pg
 
+#=================================================
+# MODIFY A CONFIG FILE
+#=================================================
+ynh_script_progression --message="Modifying a config file..." --weight=3
+
+smtp_user_pwd=$(ynh_string_random --length=24)
+url=https://$domain$path_url
+
+ynh_add_config --template="../conf/config.json" --destination="$final_path/config/config.json"
+
+chmod 400 "$final_path/config/config.json"
+chown $app:$app "$final_path/config/config.json"
+
 #=================================================
 # SETUP SYSTEMD
 #=================================================