What is Enterprise Mode?
Enterprise Mode, a compatibility mode that runs on Internet Explorer 11 on Windows 10,Windows 8.1 Update,Windows Server 2012 R2,Windows Server 2008 R2 with Service Pack 1 (SP1)and Windows 7 devices, it allows use old web applications in modern versions of IE.
To know more on Enterprise Mode please go through this Microsoft TechNet article.
This feature is missing in Windows 10 Insider Preview Build 15031:
In the Start Search type in gpedit.msc and hit the Enter key.
The Local Group Policy Editor opens.
Now locate the following:
Computer Configuration\Administrative Templates\Windows Components\Internet Explorer
Scroll down to Let users turn on and use Enterprise Mode from the Tools menu policy to edit it.
By default it remains Not configured. So Enable it to switch on to Enterprise Mode. Click OK or Apply.
Now open Internet Explorer-No Enterprise icon is available. Open Tools under Internet Explorer but again the Enterprise Mode is missing in that menu.
After failing to achieve via Group Policy editing I now tried registry edit.