diff --git a/addons/document_ftp/ftpserver/abstracted_fs.py b/addons/document_ftp/ftpserver/abstracted_fs.py
index dbda715f614..4665de89370 100644
--- a/addons/document_ftp/ftpserver/abstracted_fs.py
+++ b/addons/document_ftp/ftpserver/abstracted_fs.py
@@ -272,7 +272,7 @@ class abstracted_fs(object):
             if path.startswith('/'):
                 path = path[1:]
 
-        p_parts = path.split('/') # hard-code the unix sep here, by spec.
+        p_parts = path.split(os.sep) # hard-code the unix sep here, by spec.
 
         assert '..' not in p_parts