diff --git a/app.py b/app.py
index a4b995a..81f8759 100644
--- a/app.py
+++ b/app.py
@@ -25,11 +25,11 @@ def api_root():
                  }
 
 @app.route('/XML/', methods=["GET","POST"])
-def xml_transfer():
+def xml_transfer(self):
     try:
         #return the current config.xml
         if request.method == "GET":
-            return send_from_directory('XML','config.xml')
+            return send_from_directory(str(dir + 'XML'), 'config.xml')
 
         # set a new config.xml
         if request.method == "POST":
@@ -40,9 +40,10 @@ def xml_transfer():
             tmp_file.write(data)
             tmp_file.close()
             #check config.xml against the XSD file
-            if xml_reader.validate('/tmp/aped_device/config.xml','XML/config.xsd'):
-                shutil.move('XML/config.xml','XML/config_old.xml')
-                shutil.move('/tmp/aped_device/config.xml','XML/config.xml')
+            if xml_reader.validate('/tmp/aped_device/config.xml',str(dir + 'XML/config.xsd')):
+                shutil.move(str(dir + 'XML/config.xml'),str(dir + 'XML/config_old.xml'))
+                shutil.move('/tmp/aped_device/config.xml',str(dir + 'XML/config.xml'))
+                self.interface_handler = Interface_handler(self.xml_reader)
             else:
                 SyntaxError('the config.xml has invalid content')
             return {'error': ''}
@@ -54,7 +55,7 @@ def api_leds_control(device_name):
     try:
         if request.method == "POST":
             response = interface_handler.write(device_name,request.data.get("output"))
-            return {'output': response}
+            return {'output': str(response)}
         return {'state': interface_handler.read(device_name)}
     except Exception as e:
         return {'error': str(e)}