I’ve noticed that in Google Chrome and FireFox console the font file resources .woff throws a 404 when using @font-face CSS feature.

You will need to add a configuration to allow IIS to serve the font. In your web.config you can add the follow lines in the system.webServer block:

            <mimemap fileextension=".woff" mimetype="application/x-font-woff">

By applying this mimeType: application/x-font-woff for .woff will should fix this issue in Chrome and Firefox. This is the mimeType they request and IIS can’t work out which file type is should serve until it registered in the web.config or IIS.