Xenapp 6.5 Hotfixes - Pablo Legorreta

The following are the latest available hotfixes for XenApp 6.5 along with their highlights:

Support for Additional Communications Software: In addition to Microsoft Office Communicator and Lync, XenApp now supports the use of Web cams in conjunction with the following communication software published on XenApp 6.5 servers:
- - Citrix GoToMeeting with HD Faces
  - Skype
  - Adobe Connect

Enhanced Audio Virtual Channels: Enhancements have been made to the audio virtual channels to help reduce latency. This results in improved performance of softphones and the voice chat feature of Unified Communications applications.

Adaptive Display Settings for Smooth-running Videos and Slide Shows:Previously available in XenDesktop 5.5, Adaptive Display is now enabled by default in XenApp 6.5. Adaptive Display dynamically adjusts image quality and frame rates to deliver the best possible user experience when viewing graphics or server-rendered video content over a limited bandwidth network connection. Adaptive Display is the successor to Citrix’s highly successful Progressive Display technology. Adaptive Display is self-tuning and generally does not require configuration. However, Adaptive Display policies are available should you wish to adjust the behavior of this feature. To configure Adaptive Display on XenApp 6.5, use Windows Group Policy Editor (gpedit.msc)* and follow the procedures outlined in eDocs, the Citrix Documentation Library.* Note: At this time, Adaptive Display policies cannot be configured using AppCenter. Use Windows Group Policy Editor (gpedit.msc) instead.

Windows Media Redirection Enhanced Flow Control:Enhancements to Windows Media Enhanced Flow Control provide improved results for streamed HD videos delivered over WAN connections.OverviewFlow control is an integral part of multimedia redirection that is responsible for choosing and adjusting the rate at which multimedia data is transmitted to the client and defining a strategy to reduce the bit rate when network conditions are unfavorable. The effectiveness of the flow control implementation has a fairly large impact on the overall end user experience.
Enhancements

- End-to-End Flow Control. Video samples are no longer queued in the host-side virtual channel and instead force data to back up in the DirectShow/MediaFoundation interception filters. The major benefit here is reliability; video controls remain responsive even when network conditions are unfavorable.
- Frame Dropping. Sometimes the available bandwidth is less than the bit rate of the video being played. Frame dropping enables flow control to preserve the audio and playback synchronization at the expense of the video. It is important to note that key frames will never be dropped because these frames are often used as reference frames from which other frames will be constructed. In addition to key frames, decoders also use the last decompressed non-key frame as a reference frame. For this reason, once a non-key frame is dropped, all subsequent non-key frames are dropped (until the next key frame is found). Otherwise, the video becomes progressively noisier.

Limitations
- Frame dropping has some limitations. It is not always known ahead of time how many frames will be dropped for a given media type. Frame dropping does not typically occur until the effective network bandwidth approaches or drops below the bit rate of the media file. Users should have reasonable expectations for the user experience. In most cases, frame dropping will provide a benefit but the amount of video that is dropped can vary from media file to media file.
  - Note: Adaptive Display generally provides a better user experience than frame dropping when the available bandwidth is less than the bit rate of the video. For this reason, customers who need to deliver HD videos with bit rates of 6 or 7 Mbps are advised to set the SmartRendering Bandwidth Threshold to 8 Mbps to ensure that Windows Media Redirection is used only when there is sufficient bandwidth. For more information about setting the SmartRendering Bandwidth Threshold, see Knowledge Center article CTX124777.

Supported media formats
- WMA, WMV, ASF, MP3, Divx, Xvid, and MPEG-4. Other formats, such as MPEG-1 and MPEG-2, continue to use the old flow control.
- When using a custom Delivery Services Console as described in Knowledge Center article CTX126752, the following can be observed:
  - Client-side seamless application windows can get corrupted when moved or resized after the shadowing stops.
  - Mouse operations can be erratic when shadowing is stopped and then resumed; specifically, the mouse pointer appears to be parked in the top left corner of the session window and immediately returns to that general area after attempting to move it.
  - Note: To address this issue in its entirety, you must install both a server and a client hotfix that contains Fix #258866.

Poor performance is experienced when querying the HDX WMI Provider for specific session data on a XenApp server with 50 or more open sessions.Note: To address this issue in its entirety, you must install both a Desktop Director and an HDX WMI Provider hotfix that contains Fix #LA0563.[From XD200DDirector001][#LA0563]
Shadowing Windows XP (32-bit Edition) systems does not work.[From XD200DDirector001][#LA0695]

Poor performance is experienced when querying the HDX WMI Provider for specific session data on a XenApp server with 50 or more open sessions.Note: To address this issue in its entirety, you must install both a Desktop Director and an HDX WMI Provider hotfix that contains Fix #LA0563.[From HDXWMIPROV620W2K8R2X64001][#LA0563]

When reconnecting to a disconnected session where the wall paper is set using a group policy, the desktop wallpaper is no longer set.[From XA650W2K8R2X64011][#260318]
Users cannot connect to XenApp 6 servers when using a NOERROR licenses file on the License Server.[From XA650W2K8R2X64011][#LA0286]
After shadowing a session, the win32k.sys and vdtw30.dll files can leave the session unresponsive on the server; the session cannot be reset.[From XA650W2K8R2X64011][#LA0589]
This release is a part of the XenApp 6.5 Mobility Pack. Documentation for the mobility pack is available in eDocs at http://support.citrix.com/proddocs/topic/xenapp65-w2k8/ps-mobility-pack-landing-page.html. To install the mobility pack in its entirety, you must install:
- - Server hotfix XA650W2K8R2X64011.msp
  - Group Policy Management Console hotfixes CitrixGroupPolicyManagement_x64.msi (GPMx150WX64002) and/or CitrixGroupPolicyManagement_x86.msi (GPMx150WX86002)
  [From XA650W2K8R2X64011][#LA0881]