favicon.ico "not found error" in App Engine

If you are doing this in Java, I got rid of the error by putting a blank "favicon.ico" file in the "war" directory.

If you want to make your own quick and ugly "favicon.ico" file, this website was super easy to use: http://www.favicon.cc/

For your application, favicon.ico should be a static image. You can upload a favicon.ico file with your application, and in your app.yaml file configure your application to serve the image when the url /favicon.ico is requested. Below is an example entry in your app.yaml file for /favicon.ico. We assume you include the favicon.ico file in the directory path static/images:

- url: /favicon.ico
  static_files: static/images/favicon.ico
  upload: static/images/favicon.ico

is written here

This entry should be placed before the entry for the main handler, like:

- url: /favicon.ico
  static_files: media/img/favicon.ico
  upload: media/img/favicon.ico

- url: /robots.txt
  static_files: media/robots.txt
  upload: media/robots.txt

- url: .*
  script: main.py

The entries are processed in order of apperance and first one that matches wins.