Summary:
You have a custom HTML login page (like ADFS) that shows in the Office client applications when Office wants to authenticate a user for online resources.
This custom HTML login page fails to render correctly, either the UI does not fit right or you get JScript errors.
Cause:
Currently Office 2016 uses IE document mode 7 (aka IE7 mode) by default when rendering the HTML login page in the Office client, much HTML and JScript does not work or works differently when viewed with IE7.
Workaround:
You can force Office to use a different document mode for you page, you can work around this issue by putting this directive in your custom login HTML page.
<meta http-equiv=”x-ua-compatible” content=”IE=9″ >
If your web page is bigger than what can fit into the Office sign-in screen, you can use code similar to this to force the HTML page to stay the correct size and have scroll bars.
<DIV STYLE=”width: 460px; height: 530px; overflow: scroll”>
If you need to dynamically change the style, Office will use this token in the user agent string that you can switch off of, “MSIE 7.0”.