Citrix releases new Online Plug-in 11.2.38 for Windows with HDX Flash Redirection enhancements

Here is a quick overview of the issues Resolved in This Release:

  1. Sessions can become unresponsive while playing back Adobe Flash content in full screen mode. To enable this fix, you must set the following registry key:

    Name: EnableMessageDeadlockSafetyNet
    Type: REG_DWORD
    Data: 1


  2. This enhancement to HDX MediaStream for Flash introduces support for server-side content fetching.

    Without this enhancement, the client device is expected to retrieve Adobe Flash content directly from the network. Therefore, rendering Flash content requires the client device to have direct network access to the Flash content.  If direct access to the Flash content is not available or prohibited by IT lockdown policy, the content fails to render. With this enhancement, locked down devices can call upon the server to make the requisite content request.

    Note: To enable this enhancement, you must add and configure the HdxFlash-Client.adm GPO template included with this release. By default, the feature is disabled.

    This enhancement is included in XenDesktop 4.0. In XenApp 5 Feature Pack 2 for Windows 2003, you must also install HDXFlash110WX64 and/or HDXFlash110WX86.


  3. Client-side GPO settings for the non-Desktop Viewer and the non-Desktop Appliance case are not honored. As a result, a Flash prompt appears on the client device even if group policy for the client is set to Always/Never use HDX Flash.


  4. With HDX MediaStream for Flash enabled, YouTube video fails to render in virtual desktop sessions. This is the client-side fix that corrects the issue. To resolve the issue in its entirety, you must also install a Virtual Desktop Agent or XenApp Server hotfix that contains Fix #231288 when they become available. The hotfix is required for Virtual Desktop Agents running on Windows XP, and recommended for all other server platforms.

This limited release hotfix introduces an enhancement and fixes specific to the HDX MediaStream for Flash feature introduced with XenApp 5 Feature Pack 2 and XenDesktop 4.

Click here to download the new Citrix Online Plug-in 11.2.38 ( may require a valid account to download )