This is an issue for Microsoft Remote Desktop for macOS version 10.9.4 (2161) and likely also earlier versions. When adding a Windows user account to the 'Protected Users' security group in our ...
TaniaMariscal
Microsoft
MicrosoftStatus changed:
New
to Closed
We are sorry you are running into issues. To discuss issues we recommend to share your problem on our Tech Community forum (https://aka.ms/wvdtc) or open a support ticket after you have reviewed the troubleshooting options in our documentation (Windows Virtual Desktop troubleshooting overview - Azure | Microsoft Docs)
We recommend to review our troubleshooting section first. The other option you have is to open a support ticket through the Azure Portal.