IT and SE types should find this funny:
I use the CAD software Pro/Engineer at work every day. After a Windows Update (I eventually realized) I could no longer access our Pro/Engineer server. I eventually realized that I could not see our server from Pro/Engineer or from IE, but I could see it from Chrome.
As it turns out, Pro/Engineer's network connectivity was built on top of IE, and IE settings regarding privileges the local server had were blocking server access. I lost a healthy few hours of more productive worth to this coding curiosity.
Why, in agnostic heaven's name, would you build your software's network connectivity on an IE framwork?