The Citrix client (Citrix Receiver) running on the user’s PC normally uses the proxy configuration of the system.
Sometimes you may need to give the client a different configuration: the configuration must be performed in the Windows registry (indeed no control panel or GUI is available).
If the PCs are joined to a Windows domain, you can create a GPO (Group Policy Object) to massively configure them.
First you need the ADM file that contains all the available settings for the Receiver: the file is available in the C:\Program Files\Citrix\ICA Client\Configuration folder and it’s named icaclient.adm:
After having created a new blank GPO, import the ADM in the Administrative Templates node:
A new sub-tree is created with all the Receiver settings:
Warning – BUG
Recently I faced a bug when configuring the proxy for the Receiver through a GPO: even if a dedicated field for specifying the proxy’s TCP port is present
the Receiver seems to ignore that setting. The only way to correcty configure the port is to specify it in the Proxy host names field: