If you have enabled a virtual channels application in your Remote Desktop Services deployment, you can make this application available to client computers that access the Remote Desktop Session Host (RD Session Host) server by means of the Remote Desktop ActiveX control.

To make a virtual channel application available

1. Deploy the server-side component of the application and make sure it is running on the RD Session Host server. In the connection page of the Remote Desktop Services Web application running on your Web server, access the PluginDlls property of the IMsTscAdvancedSettings interface to specify the name of your virtual channel DLL. If you have more than one plug-in, specify a comma-delimited list of DLL names. For instance, if your virtual channel plug-in is named "MyPlugin.dll", use the following code:
   MsRdpClient.AdvancedSettings.PluginDlls = "myplugin.dll"
   

   Use the following code if you have two virtual channel DLLs. In this example, the DLL file names are "MyPlugin.dll" and "Vdriver.dll":

   MsRdpClient.AdvancedSettings.PluginDlls = "myplugin.dll,Vdriver.dll"
   

   For security reasons, the PluginDlls property only accepts a named list of virtual channel DLLs. The control returns an error if any form of file system or UNC path is specified. In addition, the names of the DLLs must contain only alphanumeric characters.

2. Ensure that the client-side component DLL of the virtual channels application is installed in the %windir%\system32 directory.

Note  By default, the Remote Desktop ActiveX control loads virtual channel client DLLs from the %windir%\system32 directory. It is possible for an administrator to change this default client plug-in DLL directory. To do so, edit the HKLM\Software\Microsoft\Terminal Server Client\vdllpath registry key on the client computer. This directory path cannot be specified in the UNC format.

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Build date: 1/14/2010