XenDesktop 7.6 + GRID Session Freeze

We are experiencing an issue with NVIDIA GRID and XenDesktop 7.6. We are running vGPU on both XenServer and vSphere 6.0 and the issue occurs on both. Intermittently throughout the day, users XenDesktop sessions appear to be frozen. The only issue is that the virtual desktop is fine. If the user disconnects then reconnects they pick up where they left off. Another way to get the session back is to resize the Citrix 4.2 receiver window to windowed mode and instantly the session comes back to life.

We have opened Citrix cases and contacted our NVIDIA reps, but nobody seems to have a fix for this yet although countless companies are experiencing the same issues. If we run XenDesktop 7.6 without the NVIDIA cards the issue goes away. There are several forum posts out there suggesting enabling legacy graphics mode and disabling desktop composition redirection to fix this. For us this is a work around and not a fix.

We cannot move to production until this issue is resolved. Has anyone here experienced and overcome this hurdle? It would be nice if NVIDIA and Citrix could work together to resolve this issue and create a runbook or install guide for the proper configuration.

I’m assuming you followed to Citrix eDoc’s for the deployment and followed the process of XenServer Tools (or VMware Tools) then Nvidia Driver followed by the HDX 3D Pro VDA?

Do you have a bug opened with Citrix or Nvidia?

Which drivers are you running in the VM?

As for the proposed workarounds.

Legacy mode will disable the use of h264, and also will not leverage the GRID SDK, giving a degraded user experience so I would not recommend trying that.

DCR is essentially sending graphics primitives to the local client to address the lack of GPU in a VM. It draws them locally and then recomposes the screen at the client. Where you have a GPU / vGPU in the VM, there’s no need to do this, and so turning it of in a vGPU enabled environment is something that I would recommend.

Thanks for the response Jason.

We have cases open with both Citrix and Nvidia.

This is a vSphere 6.0 vGPU deployment with XD 7.6. We are running the K120Q profile.

Thnkas for the note on the legacy graphics mode and DCR. These are the reasons why we keep legacy graphics mode off so the canned response from Citrix saying enable it to resolve these issues is unacceptable.

Correct, the install process was VMware tools, NVIDIA, then HDX 3D Pro.

I’ve checked with our Engineering team working on the open case, they have been unable to replicate the issue. We’ve also seen that some customers are reporting this issue with XenDesktop when there is no GPU in the VM.

We’ve passed our findings and the detailed assessment across to Citrix and it will be reviewed on today’s joint engineering call, so please continue to apply pressure onto Citrix.

When you do get a resolution, please post back here so the community can benefit from the information.


Citrix was able to provide us wit ha replacement for Hd3dProviders.dll which resolved the issue. Thanks for your assistance.

Can you give a little more detail on the resolution? I’m having a similar problem where vm’s are freezing, but if you reboot the client, all is good. I am running XD 7.6, XenServer 6.5 and have the latest Grid drivers loaded.

Hi vdi_grid,
could you please tail me that "Hd3dProviders.dll" how can i download it?, Now i have a problem same you.

Hi vdi_grid,
could you please tail me that "Hd3dProviders.dll" how can i download it?, Now i have a problem same you.

Hi vdi_grid,
could you please tail me that "Hd3dProviders.dll" how can i download it?, Now i have a problem same you.

Hi Anakhim - I would call Citrix and reference case 67692013. I am not sure they have included this in a public fix yet.



download hotfix for Hd3dProviders.dll

Anyone who can confirm changeing the Hd3dProviders.dll works?

Yes I can confirm it works like a charm.

Thank you


does anyone else have this issues with XenDesktop 7.8 ? Does this fix also work with this Version?

We experiencing this issues while implementing XenDesktop in our company.
The VM’s without a shared vGPU working fine but these with vGPU will freeze after utilizing a graphic intensive program.


just an update:
I got the same issues with XD 7.9 and opened a support ticket at Citrix.
They confirmed that CTX201616 is NOT included in 7.9!
I will update you about this.

… second update:
The escalation engineer said, fix is included in 7.9.