Introduction

This feature enhancement first appears in the XenApp and XenDesktop 7.17 Product Release. Code changes to support this feature were required in Windows VDA version 7.17 and Receiver for Windows 4.11.
Using the Receiver for Windows UI, users can now configure whether they want to show/hide the remote language bar for published application sessions.

How did the Remote language bar operate in versions prior to VDA 7.17 and Receiver for Windows 4.11?

• If only one input language was configured on the VDA, there would be no alternative language to change to, and so by design, a remote language bar would not display during a seamless published application session. Otherwise, the remote language bar would display by default.
• Administrators were able to control the appearance of the remote language bar by disabling the remote language bar agent, using a VDA-side seamless registry setting:
  HKEY_LOCAL_MACHINE/System/CurrentControlSet/Control/Citrix/wfshell/TWI/
  SeamlessFlags (0x40000) [DWORD]
• Administrators were also able to disable the ability for the user to minimize the remote language bar to the System Tray (Notification Area) by using another VDA-side seamless registry setting:
  HKEY_LOCAL_MACHINE/System/CurrentControlSet/Control/Citrix/wfshell/TWI/
  SeamlessFlags (0x20) [DWORD]

Why was the feature enhancement introduced?

Showing or not showing the remote language bar for published app sessions should be a user decision and should be configurable by the user at will. For instance, users may be taking advantage of the Keyboard Layout Synchronization feature (introduced in Windows VDA 7.12 & Receiver for Windows 4.6) and so may not require the remote language bar for published application sessions.
Administrative control using the VDA-side SeamlessFlags registry settings is not a flexible solution and does not provide a good user experience.

How does the Remote language bar operate from VDA version 7.17 and Receiver for Windows 4.11?

If only one input language has been configured on the Windows VDA, the remote language bar will not display during a published application session – there has been no change to the design from previous versions.

Users can now configure whether or not to display the remote language bar using the Receiver for Windows UI:

Feature behavior

• Users can control the remote language bar from the client endpoint.
• The seamless published application session will show/hide the remote language bar according to the current Receiver UI configuration.
• The remote language bar configuration change will take effect immediately for the current session.
• The default setting after a Receiver for Windows install is to display the remote language bar.

The VDA-side SeamlessFlags registry settings have not been deprecated and the SeamlessFlags (0x40000) will continue to prevent display of the remote language bar. In other words, it will globally disable the ability for users to control the remote language bar display from the Receiver for Windows UI.

Feature minimum requirements

• XenApp and XenDesktop VDA version 7.17 installed on supported Windows Server OS and Windows Desktop OS.
• Receiver for Windows 4.11

Limitations and considerations

At this time, RfMac, RfHtml5, RfLinux, and LinuxVDA do not include this feature enhancement. Until support is provided for these products, remote language bar display control using SeamlessFlags (0x40000) will be the only method.

Troubleshooting

Use CDFControl and MessageHistory (or Spy++) to log activity:

1. On published application session start or reconnection, the VDA will inform the client whether it supports showing/hiding the remote language bar feature.

• A new flag HOST_AGENT_FLAGS_LANGBAR_SET_CAPABLE(0x00080000) has been added in HostAgentFlags field of TWI_PACKET_START message sent when logon or reconnection to tell client that the host supports the remote language bar setting.The current client setting for showing/hiding the remote language bar is sent to the VDA.

2. The current client setting is sent to the VDA over the Seamless HDX Virtual Channel.

• The current client setting is in the form of a TWI_PACKET_C2H_SET_LANGBAR value (ShowFlag 0 = hide, ShowFlag 1 = show language bar) and received by twi3.dll (loaded by Winlogon.exe).
• The message is relayed to seamls20.dll (loaded by either WfShell.exe or PicaShell.exe, depending on whether Server OS VDA or Desktop OS VDA).

3. The client can change the remote language bar setting, even during the session.

• Again , this is in the form of a TWI_PACKET_C2H_SET_LANGBAR value (ShowFlag 0 = hide, ShowFlag 1 = show language bar)

Caution! Using Registry Editor incorrectly can cause serious problems that might 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.