Not working in MultiSite

Same with me! I now need to use theme’s setting for the time being, but favicon.ico seems to be only the problem, as frontend PNG is rendering proper URL.

Okay, the solution is:
Navigate to your Multisite:
<site>/wp-admin/network/settings.php#upload_filetypes
add ICO as a file extension!

then it works

I have tried this; it didn’t work for me! =(

So
1. you added it like:
jpg jpeg png gif mp3 mov avi wmv midi mid pdf txt ico zip
2. perhaps re-added the ico for All in one,
3. it shows in the source code,
4. it opens when you click on it in the source view
5. …but not when looking at it in the browser?
At which step it breaks for you??