In this Ask the Admin, I’ll explain how Internet Explorer 11’s Enterprise Mode can be used to fix compatibility issues with legacy web apps, along with how to configure it using Group Policy.
One of the primary reasons cited for not moving away from older versions of Windows is compatibility issues with in-house applications built around older versions of Internet Explorer. Compatibility View first appeared in Internet Explorer 8, and it aimed to fix rendering problems with pages that didn’t display correctly in the new browser.
IE determines automatically if Compatibility View needs to be enabled for a page to be displayed correctly, or users can manually add websites to be displayed using Compatibility View to a list. By default, all Intranet sites are displayed in Compatibility View, as are public webpages on Microsoft’s own list.
In Internet Explorer 11, Enterprise Mode provides high-fidelity emulation of Internet Explorer 8 and later versions, going beyond what is possible with Compatibility View alone. Some of the features of Enterprise Mode include:
- Replicating the IE8 (and later) user agent string. Although not a best practice, some legacy web applications fail if they can’t recognize the browser.
- ActiveX controls and other plugins that usually fail in IE11 will work in Enterprise Mode because it emulates the responses expected from earlier versions of IE.
- The inclusion of deprecated features no longer found in IE11, but included in earlier versions, such as CSS Expressions.
- Turns off pre-caching and pre-rendering, as many legacy web apps are not compatible with this feature.
Using Enterprise Mode and Compatibility View together increases the likelihood that your legacy app will run in IE11, while benefiting from the increased security and performance that IE11 provides. There is a slight performance hit when enabling Enterprise Mode in IE11, but it still significantly outperforms earlier versions of the browser.
Enable Enterprise Mode Using Group Policy
Unlike Compatibility View, websites cannot invoke Enterprise Mode themselves, and Enterprise Mode must be enabled in Group Policy, along with a list of sites defined in an XML file. It’s also worth noting that IE 11 Enterprise Mode requires Windows 8.1 Update or Windows 7 SP1.
The policy settings below can be configured in a local policy, or if you have an Active Directory domain, in a Group Policy Object (GPO) applied to multiple devices across your network. For more information on working with Group Policy, see Working with Group Policy on the Petri IT Knowledgebase.
Create an Enterprise Mode Site List
Before you can use Group Policy to enable Enterprise Mode, you should create a list of sites using the Enterprise Mode Site List Manager. There are two installers, one for Windows 7 and the other for Windows 8.1 Update.
- Download the appropriate version, install the tool on your PC, and then run it by double clicking the Enterprise Mode Site List Manager shortcut on the desktop.
Once the tool is installed, sites can be added one by one, imported from a previous list, or added in bulk from a comma-delimited text file. If this is your first Enterprise Mode Site List, then you might want to use a text file to import sites if there are more than a handful. If not, just click Add in the manager window, and type the site’s URL in the Add new website dialog.
The default setting is to open the site in Enterprise Mode, which uses IE8 document mode. As long as you are running IE11 with the November 2014 cumulative update installed (or later), you can choose document modes for different legacy versions of IE.
- Click Save to add the URL to the list.
- When you’ve added all the required sites to the list, click CTRL + S to save the list as an XML file. This is what the Group Policy Object will read when applying the settings on each client.
You will need to save the file to a location where clients can access it, for example to your domain’s netlogon share.
Create a Group Policy Object
Set up a Group Policy Object to enable Enterprise Mode:
- Enable the Use the Enterprise Mode IE website list policy setting under Computer Configuration > Policies > Administrative Templates > Windows Components > Internet Explorer.
- In the Options section of the policy, type the URL for Enterprise Mode Site List XML file saved in the previous steps, and then click OK.
Link the GPO to a site, domain or Organizational Unit (OU) in the Group Policy Management Console (GPMC) as required, and users should see the Enterprise Mode icon to the left of the address bar whenever they visit a site on your Enterprise Mode Site List.