This PRoblem happens because IIS does not know about woff and woff2 file mime types.

Solution 1:

Add this lines in your web.config project:

 <system.webServer>  ...  </modules>    <staticContent>      <remove fileExtension=".woff" />      <mimeMap fileExtension=".woff" mimeType="application/x-font-woff" />      <remove fileExtension=".woff2" />      <mimeMap fileExtension=".woff2" mimeType="application/font-woff2" />    </staticContent>