diff --git a/tools/scan-view/ScanView.py b/tools/scan-view/ScanView.py
index 837adae..c6dddba 100644
--- a/tools/scan-view/ScanView.py
+++ b/tools/scan-view/ScanView.py
@@ -641,7 +641,7 @@
     def send_head(self, fields=None):
         if (self.server.options.onlyServeLocal and
             self.client_address[0] != '127.0.0.1'):
-            return self.send_error('401', 'Unauthorized host.')
+            return self.send_error(401, 'Unauthorized host.')
 
         if fields is None:
             fields = {}