Citrix XenDesktop – Colors in Graphics-Specific or Intensive Applications are Not Displayed Correctly

This article applies for Citrix XenDesktop 5.5 and Citrix XenDesktop 5.6

Symptoms

Adobe Photoshop, or any graphics-specific or intensive application, is not representing color correctly in a XenDesktop session.

Cause

Graphics undergo compression and caching when transferred to the client.

Resolution

Remove Off-Screen Surfacing from the applications which are not representing color correctly in the XenDesktop session.

Caution! This fix requires you to edit the registry. Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Citrix cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk. Be sure to back up the registry before you edit it.

On the VDA that hosts the application, add the following registry key and value:
Key: HKEY_LOCAL_MACHINE\SOFTWARE\Citrix\ICA\Thinwire
Value: DisableOssForProcesses
Type: REG_SZ
Data: photoshop.exe

This is a sample registry file contents:
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Citrix\ICA\Thinwire]
“DisableOssForProcesses”=”photoshop.exe”

More Information

Multiple applications can be listed as data in the registry. Separate multiple process names with semicolons. The following is a sample registry file with multiple applications:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Citrix\ICA\Thinwire]
“DisableOssForProcesses”=”photoshop.exe;indesign.exe;illustrator.exe”

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