MS recommended GPO impact on Citrix Browser content redirection

Virtual Apps and Desktops

On 1 of my current project I was facing issue with offload not working with Internet Explorer.

I spent time to find the solution and will provide you more information here after

Environment

The environment is composed on Windows 10 Enterprise version 1803 VDA hosted in Azure Cloud.

The initial SOW for the project stands to not reuse customer’s GPO and start from scratch with Microsoft Recommended one for:

  • Windows 10 1803
  • Internet Explorer
  • Office 2016

BTW, the customer was having +160 GPOs in place, with some specific IE settings that were needed for day to day production.

So I extracted all the specific IE settings (Computer and User) and create a new GPO.

When it came to Offload testing I was seeing issue.

It was not working … and when playing YouTube video, the CPU was going crazy.

 

The issue

My first though was about the MS IE recommended settings so I remove the User GPO IE and test, still having the issue.

I then remove the Computer GPO for IE and test was successful.

One sure thing was that a setting from MS recommended settings in Computer GPO was creating the issue.

The point here is that this Computer GPO contains a lot of settings.

One quick way to see if Offload is working is to check the CtxGfx.exe process in Task Manager.

It should stay to 0% CPU consumption when you play a Video on YouTube even in full screen.

 

My issue

Based on previous explanation, here after a screenshot of my issue.

As you can see when a Video is played the CPU usage for CtxGfx.exe is growing, even if the video is not played in full-screen.

 

Analyze

After time and time spent on this, if figure out that the issue which was coming from MS recommended settings for Computer was caused by 1 setting only!

This setting is the following:

Turn on 64-bit tab processes when running in Enhanced Protected Mode on 64-bit versions of Windows

As you can see in the following screenshot (part of the GPO), the MS recommended settings stand to Enable this setting

 

Tests

To validate that was the setting which create the issue, I made a quick test on another VDA (from other Customer) where it was working.

The test was to enable this setting, close an re-open the browser.

Doing that, on the opening I received a message:

The fact here is that the above message will appear only with the 64-bit version of Internet Explorer, with the 32-bit you not see the message however offload will not work.

The Citrix HDXJsInjector is a 32-bit plugin so if the setting from MS is set to Enable, this plugin will not load and shown as Incompatible

 

Hope this article will help you understand how to validate Video Offload and save time in case of issue.

 

Thanks

Arnaud