Windows 10 Remote Desktop sound/drive redirection not working

The solution to this problem was that the following service was disabled:

Remote Desktop Services UserMode Port Redirector

After enabling this service and setting to automatic (by pressing win + r and opening services.msc) all was working again.

Edit:

@SemVanmeenen in the comments mentions that restarting the Windows Audio service on the host fixed it for them, and it appears to fix the issue for a lot of other people too.

As @SemVanmeenen mentioned, restarting the Windows Audio Services (I used the AudioEndpointBuilder as this is the root service) worked for me. This is a case I see often and results in Windows beeing unable to "pick up" the new device registered by the RDP Port Redirector.

Thus I think we're seeing different root causes here, as restarting the Audio Services forces the system to pick up the new Audio Devices, while the RDP Port Redirector creates those devices in the first place. This service of course has to be enabled for audio redirection to work

For the German users out there, the RDP Port Redirector is called "Anschlussumleitung für Remotedesktopdienst im Benutzermodus" in German in case you're looking for it...