We have found that many sites built with the WAB do not work or us in Internet Explorer. The version doesn't matter, it can fail in IE 9, 10 and 11. In IE, we just get a white screen and the app doesn't load. Looking at the http traffic, there are no failed requests. But looking at the console we see the attached "Access denied" messages that refer to <name>.maps.arcgis.com. The sites always work for us in Chrome an FF.
When we were first developing and testing WAB applications on our intranet, we found that some of us had to add the intranet server to IE's "Trusted sites" list in order or it to work. When we published out first WAB app on the internet (http://gismaps.kingcounty.gov/iMap) we found we had to add that server to IE's trusted sites list in order for it to work for us, but only when using our work computers on our work network. We can connect to a public network using the same browser and computer and the site would work.
Now we get emails from some members of the public saying they are getting nothing but a white screen, while others seem to have no problem. It seems to me that there is some combination of IE security settings and perhaps our firewall that causes this. We've been telling people to try adding our site to their "trusted sites" list, but that is not only annoying but also not possible for many people who have an IT department that prevents them from changing their own settings. Plus that solution only works on a site by site basis, it doesn't solve the larger issue.
I'd like to know if other people have this problem and if anyone can help to figure out a solution. Here are some of the sites that do not work for us in IE on our network, but work fine in Chrome and FF (and in IE from home). In each case I can see that access denied error in the IE console. Please note we have *.ArcGIS.com in our trusted sites list.