HDX Realtime video compression was a feature that Citrix added to their XenApp/Xendesktop. It uses compression and its blend of herbs and spices to lower the bandwidth requirement for webcams, while keeping fidelity.
While this sounds all good, it some cases you need to use good ol USB plug in play for compatibility. By default, Xendesktop will try to use the HDX Realtime video compression (which shows up as ‘optimized’ under Devices in citrix receiver). In our case, when using the HDX realtime compression, the recording software would complain that the device wasn’t available. However, switching to Generic (ie USB plug n play) everything would work just fine.
There is not an easy way to force the Generic method over the Optimized method. The user can switch it, sure, but we want the users to log in and go, not fiddle with settings every time they log in.
It may be that the web camera was unsupported (is that possible nowadays?) but in any case, administrators need a way to force this via Citrix HDX policies. There wasn’t, at least not that I could find.
After searching, we found the answer.
This settings forces Generic usb redirection first, before trying to use the Optimized metho.
Edit: Updated the key path, typos
Disclaimer: Usual stuff, I’m not responsible if this breaks things, be sure to back up your Registry just in case.