Product Documentation

Known Issues

Oct 01, 2013


  • When using Receiver for Windows 3.0, your users may have problems logging off or shutting down while their VDA windows are open. It is recommended that you upgrade your users to Receiver for Windows 4.0. [#16698]
  • Call forwarding is not available in this release. With the HDX RealTime Connector installed and the Lync native voice and video calling disabled (TelephonyMode = 5), the Lync Call Forwarding functionality is disabled.
  • The Lync Optimization Pack is not available to work with the hosted version of Microsoft Lync (Office 365). This issue is fixed in version 1.4.100.
  • When Remote PC is enabled on a device and you try to start the RealTime Connector and the RealTime Media Engine from the device, you might have to wait a short period of time for the RealTime Media Engine to initialize. Wait about one minute before you try to place a call. [#14438]
  • Users cannot place themselves on hold in a conference call if they are connected by way of Citrix Access Gateway and UDP is blocked for the user. The users see the "The system could not place the call on hold. Please try again." error. The calls remain up. The workaround is for the users to hang up and then call back. [#14436]
  • When the HDX RealTime Connector is running on a Windows XP system employing a VPN and an additional network adapter, DNS resolution of the SIP server and SIP proxy server host name may fail. SIP server host names are typically resolved by way of internal DNS, rather than external DNS. Some VPN implementations might circumvent effective DNS resolutions. To resolve this problem, add the domain name of the Internal Server and External Server to the Windows XP HOSTS configuration: c:\windows\system32\drivers\etc\hosts.
  • When you run the RealTime Connector in a XenDesktop session, the user device or the XenDesktop host may block traffic to or from the RealTIme Media Engine host. You might see an error message such as "RealTime Connector is waiting for the connection from the Media Engine… or "Failed to maintain RealTime Connector on this device. Communication to the Media Engine was disrupted. Please contact your system administrator." In such cases, create an exception in the Windows firewall.
  • When attempting to make high-definition video calls from a home office, take into account your user’s network bandwidth and ISP routing policies. If you observe pixilation of the video or problems with lip sync, adjust the Maximum Packet Size (MTU) on the network interface card properties to a lower value such as 900 to avoid situations where ISPs perform traffic shaping based on packet size.
  • Occasionally on devices running Linux Ubuntu 11 on 32-bit systems, you can experience poor video quality—namely flickering image—during a call. To improve video quality, increase foreground and decrease background lighting and adjust the anti-flicker setting on the transmitting camera.
  • On some HP T610 terminals running Ubuntu 10.4 Linux operating system, the PulseAudio network sound server may not start at system initialization or become disabled during operation. In such cases, contact HP to receive the latest version of their terminal software.

HDX RealTime Media Engine

  • Sometimes, when attempting to install the HDX RealTime Media Engine on Windows, a message indicates that there is no available disk space. However, limited space does exist on the Z:/ drive of the terminal. This is a known issue for Microsoft installers and applies to the Citrix Receiver as well.
  • If the screen saver is not disabled by the Citrix HDX RealTime Media Engine during an active call on a Linux terminal, the RealTime Media Engine disconnects the call. To work around this problem, move the mouse occasionally or call back. [#16110]
  • The RealTime Media Engine software rejects incoming call attempts sent from the LifeSize Express 220 without signaling an incoming call dialog to the user. [#14762]
  • During installation or un-installation, it is possible to encounter certain error conditions where the error message string is not localized. [#14530, #93]
  • When a user who is using a Plantronics Blackwire™ C620-M audio headset device attempts to answer an incoming call by pressing the button on the chord, the terminal and XenDesktop freeze. At this time, we recommend against using this device with the HDX Optimization Pack. Users who have this device should answer the calls only using the incoming call dialog that appears in the RealTime Connector. [#14526]
  • When calls end abnormally on a Windows or Linux device, error messages appear as text overlaid on top of the video display. However, on a Macintosh computer used as a terminal device, when certain errors during a call cause that call to fail, the video window immediately closes and you cannot view the error string. [#14515]
  • Currently, Lync-certified USB phones like the Polycom CX300 and Plantronics P240-M are supported merely as Audio devices, with no support for the buttons, ringer, or display.[#14253]
  • The Mute button/function is not available on a Plantronics Blackwire C620-M. This is because the device does not adhere to the Lync protocol specification. [#14165]
  • In Seamless mode, the following issues exist for Full Screen video:
    • Full Screen video appears in letterbox format with the Linux version of the RealTime Media Engine in Seamless mode. [#13564]
    • The Full Screen Control hides behind other apps in a Seamless session in XenApp Seamless mode. [#10731, #3]
  • In some cases, when a user opens the Video page of Tools > Audio Video Settings, the display presents a black preview window, and the RealTime Connector does not display video during a call. This problem has been observed in the following environment: a terminal device running SUSE Linux Enterprise Desktop (SLED) 11 SP1 and XenDesktop servers running Windows7. The problem occurs because the RealTime Media Engine requires an accelerated video driver to use the XVideo extension. The standard SLED 11 SP1 distribution may not include that driver. As a result, no video is rendered on the terminal screen. To resolve the problem, update to SLED 11 SP2, which contains the required driver to render the video normally.

HDX RealTime Connector

  • Some report that video disappears (black screen appears) several times during the first 5 seconds just after conference creation. Others have reported a green frame displayed during the initial few seconds of video. This problem goes away after a few seconds. [#16312]
  • When you use a Macintosh laptop as a terminal, your built-in camera does not work when the HDX RealTime Connector is in non-optimized (fallback) mode.
  • Lync Native calling is disabled by default. However, if the administrator enables Lync Native calling, you can accept a call using Lync Native calling when the HDX RealTime Connector is installed. To prevent this, make sure that built-in Lync calling is disabled when running the Citrix HDX Optimization Pack.
  • When switching between terminals connecting to the same XenDesktop, sometimes the RealTime Connector will fail to start the RealTime Media Engine and connect with it properly. The software displays a popup message with error code 70. The workaround is to restart Lync, which then restarts the RealTime Connector and it will connect properly. Note that this issue is fixed in version 1.4.100. [#14039]
  • Selecting a device and then navigating to the advanced tab and back to the device tab causes the selected device to revert to the one that was originally selected. The workaround is to exit the dialog after selecting the new device. [#13450]
  • The RealTime Connector can stop working after launching XenDesktop while the RealTime Connector was launched earlier (after sleep mode on terminal). The workaround is to restart Lync in the XenDesktop session. [#63]