I just loaded ArcGIS Maps for Office 4.1 and it only gives me a blank Sign-In popup (title says "Sign in to the ArcGIS Platform") so something is not working right or blocking it. I have added arcgis.com and my org page to trusted sites - still blank.
I have Windows 10 with Office 2013 (32-bit) and loaded the AGMFO x86 version. Toolbar shows. I did notice during install that it did not find Office 2013 and proceeded to load MS Visual Studio 2010 Tools for Office, but seems to have been successful.
Any ideas why I get the Sign-In popup but no entry boxes?