diff --git a/preview_easy/controllers/preview.py b/preview_easy/controllers/preview.py
index 33154faf5..d6600cb38 100644
--- a/preview_easy/controllers/preview.py
+++ b/preview_easy/controllers/preview.py
@@ -34,7 +34,7 @@ class preview(http.Controller):
             #         result = mammoth.convert_to_html(file)
             #         html = result.value
             #     return template.render(html=html)
-            elif attach.mimetype in [excel, word]:
+            elif attach.mimetype in excel or word:
                 office_view_url = 'http://view.officeapps.live.com/op/view.aspx?src='
                 base_url = request.env['ir.config_parameter'].sudo().get_param('web.base.url')
                 html = f'{office_view_url}{quote(base_url + "/web/content/office_preview/" + str(attach.id))}'