I recently had a request for a user to be able to toggle between different applications inside their Citrix desktop session with alt+tab. The Citrix receiver provides this functionality with a registry change. There are a couple ways to send the hot key combo of Alt+tab to the Citrix session, but below I will show how to pass the physical hot key combo of Alt+tab from the client workstation to the Active Citrix session window (non-fullscreen mode).
This work will be done on the Client workstation and I am assuming the client has Windows 7 with Citrix receiver installed.
My background information was found here:
http://support.citrix.com/article/CTX118974
http://support.citrix.com/proddocs/topic/ica-settings/ica-settings-transparentkeypassthrough.html
1. Open regedit on the client device to edit the registry
2. Navigate to the key
HKEY_LOCAL_MACHINE \SOFTWARE\Citrix\ICAClient\Engine\Lockdown Profiles\All Regions\Lockdown\Virtual Channels\Keyboard\
3. Open Key: TransparentKeyPassthrough
4. Set the value to: Remote
5. Exit the Citrix receiver if it is started and log back into your Citrix desktop.
6. When the Citrix desktop session is the Active window, you will be able to toggle between the applications in that session with Alt+Tab
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