Microsoft EDGE browser ignoring Enterprise Mode li

Question

Since EDGE seems to be the "default" browser for Windows 10, we need a way to "force" EDGE to open our website in IE mode or at least direct the user to open the website in IE.
EDGE seems to ignore the "X-UA-Compatible" meta data and the website we are hosting is a "Microsoft" built in remote application service that uses Microsoft Remote Desktop so that means "ActiveX controls".
We tried to use "Enterprise Mode" https://msdn.microsoft.com/en-us/library/Dn872481.aspx but that does not seem to work with EDGE and that is really not a good fix since we don't have control of group policies on machines outside our domain.
Our only option right now is to tell users to set their default browser to IE but that is a lame option.

Answer 1

So far the articles https://technet.microsoft.com/en-us/library/mt270205.aspx and https://msdn.microsoft.com/en-us/library/Dn872481.aspx are misleading and don't fully work on my machine.
There are two options I was able to get to work.

1. Group policy & XML site list
   The articles say to use "Administrative Templates > Windows Components > Internet Explorer > Use the Enterprise Mode IE website list. This did not work for me.
   BUT "Administrative Templates > Windows Components > Microsoft Edge > Allows you to configure the Enterprise Site List" did work for me.
2. Group policy & Intranet Site
   The article said to use "Administrative Templates > Windows Components > Microsoft Edge > Send all intranet traffic over to Internet Explorer" which did not work
   UNLESS you also go into "Internet Explorer > Tools > Options > Security > Local intranet > Sites > Advanced" and then add the site to the list.
   The article is assuming that the user knew to do this step!

Here is the registry keys just in case someone wants to do all this without opening group policy / IE options.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\MicrosoftEdge\Main]
"SendIntranetTraffictoInternetExplorer"=dword:00000001

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Policies\Microsoft\MicrosoftEdge\Main]
"SendIntranetTraffictoInternetExplorer"=dword:00000001

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap\Domains\google.com\www]
"https"=dword:00000001

Answer 2

Please, read this document updated about Enterprise Mode List for Edge: https://technet.microsoft.com/en-us/library/mt270205.aspx

As you can see there, now you have to play with Group Policies

Answer 3

Microsoft Edge doesn't have any other "document modes" besides its native one, so it ignores X-UA-Compatible.

I can think of three options:

1. Try to get your site added to Microsoft's compatibility list, so Edge asks visitors to open the site in IE. (I see you commented on Is there any method for opening specific web app by Internet Explorer from MS Edge browser? so you have probably already tried this.)

2. Get your site working in Edge. This may or may not be possible depending on if it uses any IE-specific features. (Does it work in Firefox or Chrome?)

3. Use user agent detection to display a warning message to users who aren't using Internet Explorer (look for the absence of the "Trident/" string.)