Appendix A: Frequently Asked Questions and Troubleshooting Tips

Applies To: Windows Server 2008 R2 with SP1

Why is the virtual machine connection console disconnected when RemoteFX is enabled?

In Windows 7, 3D video adapters are accessible in the console session only and not in the remote session. Due to this limitation, Remote Desktop Services is unable to serve a remote session that has access to the RemoteFX 3D Video Adapter. To work around this issue, the console session is sent to the user remotely. Because two console sessions cannot exist, the virtual machine connection console is disconnected. If for some reason the system falls back to standard VGA, the virtual machine connection console is reconnected.

If you need to access the virtual machine from the Virtual Machine Manager console, you can shut down the virtual machine, uninstall the RemoteFX 3D Video Adapter, and then restart the virtual machine.

How can I tell if my GPU has sufficient video memory?

The RemoteFX server and the RemoteFX-enabled virtual desktops must meet the RemoteFX hardware requirements. For information about the hardware requirements for deploying RemoteFX, see Hardware Considerations for RemoteFX.

How can I tell if my Remote Desktop session is using RemoteFX?

You can confirm that your Remote Desktop session is using RemoteFX as follows:

  • Check the event log inside the virtual machine. Event ID 2 in the Microsoft-Windows-RemoteDesktopServices-RdpCoreTS/Admin event source is written to the event log with the following text “Remote Desktop Protocol will use RemoteFX module to connect to the client computer. RemoteFX module is being used based on the server configuration, client configuration, and network connection.”

  • If the Start Menu shows the Shut Down button, you are using RemoteFX. If you are not using RemoteFX, Log off will appear on the Start Menu.

Are multiple GPUs supported on a single RemoteFX server?

A maximum of 4 GPUs are supported on a single RemoteFX server. However, the GPUs must be identical. Installing multiple GPUs from different vendors on one RemoteFX server is not supported.

Note

If you manage a KVM switch over IP with an onboard management adapter, install the RemoteFX cap driver once you have enabled RemoteFX. The RemoteFX Cap driver supports KVM access over IP prior to the point where the Windows operating system loads (so that you can access the BIOS). Once the operating system has loaded, you can access the RemoteFX server by using RDP or a non-Microsoft solution for KVM management over IP.

Troubleshooting

The following error message appeared when I attempt to start the selected virtual machine(s): “Failed to power on with error ‘Unspecified error.’”

It is likely that you are attempting to start RemoteFX virtual machines on a server that does not have a Second-Level Address Translation (SLAT)-enabled processor.

The following error message appeared when I attempted to start the selected virtual machine(s): “Microsoft Synthetic 3D Display Controller failed to power on.”

It is likely that you are attempting to start more virtual machines than your GPU can support. In the event log on the host server, verify if there is an event that indicates the server has insufficient GPU resources to start the requested virtual machine.

An error message appeared when I attempted to start the selected virtual machine(s).

If the virtual machine fails to start after you enable the RemoteFX 3D Video Adapter, ensure the following:

  • You have downloaded and installed a recommended version of the latest driver for the GPU from the vendor’s website. For a list of recommended GPU drivers, see this Beta testing Microsoft RemoteFX in Service Pack 1 (https://go.microsoft.com/fwlink/?LinkID=197417).

  • You have disabled any GPUs with an XDDM driver. If you manage a KVM switch over IP with an onboard management adapter, install the RemoteFX cap driver once you have enabled RemoteFX. The RemoteFX Cap driver supports KVM access over IP prior to the point where the Windows operating system loads (so that you can access the BIOS). Once the operating system has loaded, you can access the RemoteFX server by using RDP or a non-Microsoft solution for KVM management over IP.

  • Active Directory Domain Services are not enabled on the RemoteFX server. Running Active Directory Domain Services on the RemoteFX server is not a supported configuration.

  • The following Group Policy settings must be disabled:

    • Computer Configuration/Windows Settings/Security Settings/Local Policies/Security Options/Interactive Logon: Message text for users attempting to log on

    • Computer Configuration/Windows Settings/Security Settings/Local Policies/Security Options/Interactive Logon: Message title for users attempting to log on

Hyper-V Manager stops responding when I attempt to create a new virtual machine or edit settings on an existing virtual machine.

If the Hyper-V Manager console, svchost.exe process, or RDVGSM service consistently stops responding when you attempt to create a new virtual machine or edit settings on an existing virtual machine, verify that the following Group Policy settings are not configured on the RemoteFX server:

  • Computer Configuration/Windows Settings/Security Settings/Local Policies/Security Options/Interactive Logon: Message text for users attempting to log on

  • Computer Configuration/Windows Settings/Security Settings/Local Policies/Security Options/Interactive Logon: Message title for users attempting to log on

Also, verify that the RemoteFX for RD Virtualization Host server is not a domain controller. You cannot install the RD Virtualization Host role service on a domain controller.

The following error message appeared after I install the virtual GPU: “Connection was denied because the user account is not authorized for remote log on.”

All users (even users who are part of the Administrators group on the virtual machine) who need to log on to a virtual desktop that has a RemoteFX 3D Video Adapter need to be members of the Remote Desktop Users group.

I am unable to connect to the RemoteFX virtual desktop. Connection is denied even though Remote Desktop access is enabled.

A new Windows Firewall rule is added for RemoteFX. If you perform a new installation and enable Remote Desktop by using the System properties sheet, the rule is enabled automatically.

You must enable the RemoteFX Windows Firewall rule manually if you do either of the following:

  • Enable Remote Desktop by using the netsh command or the Windows Firewall APIs.

  • Upgrade to Windows 7 with SP1 on a virtual desktop that already had Remote Desktop enabled.

Performance is slow when I use my RemoteFX virtual desktop.

Ensure that hyper-threading is enabled in the BIOS on your RD Virtualization Host server. RemoteFX is optimized for usage over a LAN connection, so ensure that you are using at least a 10 Mbps connection with less than 20 milliseconds of latency between the client computer and the virtual machine. Also ensure that Windows Aero is configured on the RemoteFX-enabled virtual desktops.

I see artifacts on my RemoteFX-enabled virtual desktop.

Ensure that you have enabled the Windows Aero desktop experience on the RemoteFX virtual machines. There is a known issue in the Windows Server 2008 R2 with SP1 Beta release where you may see screen artifacts when Windows Aero is not enabled.

My RemoteFX-enabled session defaults to a single monitor session.

The RemoteFX 3D Video Adapter supports a fixed set of resolutions. Your RemoteFX-enabled session may default to a single monitor session under the following conditions:

  • If you request a resolution that is not supported, RemoteFX defaults to a single monitor session at a lower supported resolution.

  • If you request a resolution that is higher than the maximum resolution assigned to that virtual desktop, your session will default to a single monitor session at a lower resolution.

  • If you request a greater number of monitors than the maximum number assigned to a virtual desktop, your session will default to a single monitor session.

An event is logged for RemoteFX-enabled virtual machines: Using CPU to compress because of insufficient GPU resources

Ensure that you have enabled the Windows Aero desktop experience on the RemoteFX virtual machines. There is a known issue in the Windows Server 2008 R2 with SP1 Beta release where you may see screen artifacts when Windows Aero is not enabled.

If the GPU card is overloaded, RemoteFX encoded content can fall back to use the processor for encoding in RemoteFX-enabled session instead of the GPU. This can reduce the performance on the RemoteFX server. You should consider moving some RemoteFX-enabled virtual desktops to a different RemoteFX server.