First published on TechNet on Nov 30, 2016 Are you using Mozilla Firefox to access the Intune Admin console and work on scenarios such as Android for Work or Volume Purchasing? If so, you may run into an issue due to recent change in Firefox to prefer XML over JSON. There’s a one-time workaround to change the default behavior of the browser; the fix below is from Brock Allen’s blog post :
In the address bar in FireFox, type “about:config”.
Click the “I promise” button.
In the search bar type “network.http.accept.default”.
Double-click the setting.
In the comma-separated list add a new value of “application/json” (without the quotes) . Replace with “application/json;q=0.9” or another value of your preference.
Note that Mozilla will be removing support for Silverlight in version 52 of Firefox, effective March 2017. Please refer to the documentation page here for more information on supported browsers.