The Endpoint Analysis (EPA) plugin fails on NetScaler Gateway virtual server, when using Internet Explorer 11 (IE 11) with Microsoft hotfix KB3025390 installed.

After installation of the Microsoft hotfix, you will be directed to a page where you can either "Download" the plugin or "Skip Check" in some builds. The EPA plugin does not run as expected.

To fix this issue, complete the following procedure:

1. Using a secure copy program like WinSCP, connect to the NetScaler and edit the following files as follows:
   Note: It is highly recommended to back up these two files to your local computer before proceeding with any changes.

   /netscaler/ns_gui/epa/epa.html
   /netscaler/ns_gui/vpns/postepa.html

   WinSCP has the ability to edit files by right-clicking them and choosing Edit.

   

2. Both of the preceding files contain the text, “document.location,” search for this text in both epa.html and postepa.html and change it as shown in the following example:

      epaActiveX.StartEpa(ns_getepacookie("NSC_EPAC"),
                            document.location,
                            nstrace,
                            nsvip,
                            nsversion,
                            navigator.userAgent + ", " +;

Change this text to “document.location.href,” in each case and save the files.

epaActiveX.StartEpa(ns_getepacookie("NSC_EPAC"),
                       document.location.href,
                       nstrace,
                       nsvip,
                       nsversion,
                       navigator.userAgent + ", " +

3. To ensure that this fix stays consistent after a reboot of NetScaler, perform the preceding changes to the following files too:

   /var/netscaler/gui/epa/epa.html
   /var/netscaler/gui/vpns/postepa.html

   Note: The difference here is the "/var/" directory.

4. Instruct the affected users to clear the internet browser history/cache. The following items at a minimum must be cleared.

   

5. Close the browser and retry the connection. You should see the EPA plugin start.

   

Problem Cause

The installation of Microsoft hotfix KB3025390 changes how IE 11 views certain objects and thus causes this issue.