The DPI Synchronization feature ensures that the DPI value in a remote session changes to match the DPI value of the client system when you connect to a remote desktop or published application.

Note: The DPI synchronization feature is not supported on Raspberry Pi devices.

When the DPI Synchronization feature and the Display Scaling feature are both enabled, only one feature takes effect at any given time. Display scaling occurs only when DPI synchronization has not yet taken effect (that is, before the DPI setting on the remote desktop matches the DPI setting on the client system), and display scaling stops working after the DPI settings match.

The DPI Synchronization agent group policy setting determines whether the DPI Synchronization feature is enabled. The feature is enabled by default.

Behavior of DPI Synchronization with Remote Desktops

The default DPI synchronization behavior depends on the Horizon Agent version that is installed in the agent machine.

Beginning with Horizon Agent 2012, the client's per-monitor DPI setting is synchronized to the agent and changes take effect immediately during a remote session by default. This feature is controlled by the DPI Synchronization Per Monitor agent group policy setting. The DPI Synchronization Per Monitor feature is supported by default for virtual desktops and physical desktops. It is not supported for published desktops.

With earlier Horizon Agent versions, Horizon Client supports synchronization only to the system DPI setting. DPI Synchronization happens during the initial connection, and Display Scaling works in case of reconnection, if necessary. When DPI Synchronization works and the client system's DPI setting matches the remote desktop's DPI setting, Display Scaling cannot take effect, even if you toggle the Allow Display Scaling option to on in the user interface. Windows does not allow users to change the system-level DPI setting for the current user session, and DPI synchronization occurs only when they log in and start a remote session. If users change the DPI setting during a remote session, they must log out and log in again to make the remote desktop's DPI setting match the client system's new DPI setting.

The agent DPI setting is located in the Windows registry at Computer\HKEY_CURRENT_USER\Control Panel\Desktop: logPixels.

Note: The system DPI setting might not be the same as the main monitor's DPI setting. For example, if you close the main monitor and the system switches to an external display that has a different DPI setting than the main monitor, the system DPI setting is still the same as the DPI setting of the previously closed main monitor.

This version of Horizon Client does not support the DPI Synchronization Per Connection agent group policy setting, which is provided with Horizon Agent versions 7.8 through 2006.

For more information about the DPI synchronization group policy settings, see the Configuring Remote Desktop Features in Horizon document for your Horizon Agent version.

Supported Guest Operating Systems for Virtual Desktops

For virtual desktops, the DPI Synchronization feature is supported on the following guest operating systems:
  • 32-bit or 64-bit Windows 7
  • 32-bit or 64-bit Windows 8.x
  • 32-bit or 64-bit Windows 10
  • Windows Server 2008 R2 configured as a desktop
  • Windows Server 2012 R2 configured as a desktop
  • Windows Server 2016 configured as a desktop
  • Windows Server 2019 configured as a desktop
Note: For Windows server machines that are configured as a desktop, the DPI Synchronization Per Monitor feature is not supported.

Supported RDS Hosts for Published Desktops and Published Applications

For published desktops and published applications, the DPI Synchronization feature is supported on the following RDS hosts:
  • Windows Server 2012 R2
  • Windows Server 2016
  • Windows Server 2019
Note: For RDS hosts, the DPI Synchronization Per Monitor feature is not supported. This limitation does not apply to published applications that run on desktop pools with the VM Hosted Applications feature.

Tips for Using DPI Synchronization

Use the following guidelines when working with DPI Synchronization.

  • If you change the DPI setting on the client system, but the DPI setting does not change in the remote desktop, you might need to log out and log in again to make Horizon Client aware of the new DPI setting on the client system.
  • If you start a remote session on a client system that has a DPI setting of more than 100 percent, and then use the same session on another client system that has a different DPI setting of more than 100 percent, you might need to log out and log back in to the remote session on the second client system to make DPI synchronization work on the second client system.
  • If a Horizon administrator changes the DPI Synchronization group policy setting value for Horizon Agent on a Windows remote desktop, you must log out and log in again to make the new setting take effect.