Hi,
What's your Windows OS version? You can run winver in CMD to show the OS version.
Was your MS Remote Desktop App the Windows Desktop client or Windows 10 Client in the Microsoft Store?
https://learn.microsoft.com/en-us/windows-server/remote/remote-desktop-services/clients/remote-desktop-clients
As per the official document, the latest version of Windows Desktop client is 1.2.1670. And for Microsoft Store Client, the version is 10.2.1534.
https://learn.microsoft.com/en-us/windows-server/remote/remote-desktop-services/clients/windowsdesktop-whatsnew#updates-for-version-121670-insider
https://learn.microsoft.com/en-us/windows-server/remote/remote-desktop-services/clients/windows-whatsnew#updates-for-version-1021534
I am not sure if there is any delay in the offcial document. But I think you can use above links to download the appropriate version for your computer.
Since both MS Remote Desktop Preview App and MSTSC.exe work well, and the error only occurs on Remote Desktop version 10.2.1798, we suggest that you could report this issue to Remote Desktop UserVoice.
Thanks,
Eleven
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