When accessing Portal for ArcGIS 10.4 navigation links in the Portal Home application in Internet Explorer, enabling Compatibility View displays a runtime error

Description

When using Internet Explorer in Compatibility mode, navigation links in the Portal for ArcGIS Home application fail to open. The URL in the search bar is duplicated, and the Portal returns a runtime error.

Cause

This is a known issue. BUG-000095013: When accessing Portal for ArcGIS 10.4 in Internet Explorer, enabling Compatibility View in the browser causes Internet Explorer to display a runtime error when accessing the main links at the top of the page, such as Gallery, My Content, and so on.

Workaround

If unable to turn off Compatibility View, update the ArcGIS Web Adaptor associated with the Portal's web.config. Adding the X-UA-Compatible HTTP header to outgoing responses, no matter the load balancer or reverse proxy being used, solves the issue. 

Update the web.config file as follows:

<system.webServer>
<httpProtocol>
<customHeaders>
<clear />
<add name="X-UA-Compatible" value="IE=11" />
</customHeaders>
</httpProtocol>
</system.webServer>