diff --git a/trytond/webdav/webdav.py b/trytond/webdav/webdav.py
index 9817f49981..cdb8edc842 100644
--- a/trytond/webdav/webdav.py
+++ b/trytond/webdav/webdav.py
@@ -709,7 +709,7 @@ class Attachment(ModelSQL, ModelView):
         super(Attachment, cls).__setup__()
         cls._error_messages.update({
                 'collection_attachment_name': ('You can not create an '
-                    'attachment named "%(attachment)s in collection '
+                    'attachment named "%(attachment)s" in collection '
                     '"%(collection)s" because there is already a collection '
                     'with that name.')
                 })