Microsoft RDP client for Mac receiving "Unable to connect" error code 0x5000007 from Microsoft RD Gateway

If you have a good rapport with your IT support team then ask them if you need to install an SSL certificate on your Mac. My understanding is the RD Gateway requires this for RD clients to connect successfully. The other aspect of this is whether you have to establish a VPN first. Now this may or may not be a requirement prior to using MRD but its worth asking.

I've had another look and found this:

https://remotedesktop.uservoice.com/forums/925639-remote-desktop-beta-client-for-ios/suggestions/39205006-rd-gateway-error-0x3000066

Ask if TLS v1.2 is enabled and make sure you're on the latest macOS. Worth a try?

Good luck!

This forum is for Apple's Remote Desktop and therefore not for you. Microsoft's Remote Desktop forum is here:

https://remotedesktop.uservoice.com/forums/287834-remote-desktop-client-for-mac

You should have a word with your network administrator and ask them the question. FWIW I think there's a certificate or a protocol setting that needs to be configured somewhere that will allow your Mac to 'pass-through'. This could be something built-in on a PC or pre-configured when your IT department roll out the setting to their PC clients. Be patient and persistent and don't let them fob you off simply because you're on a Mac and not a PC. They should be supporting you properly irrespective of platform. It's their job after all