1.0x704 means The specified port is unknown.
In general, we need to open 3389 RDP port in windows firewall on AWS server.
2.If we install Microsoft Remote Desktop Beta for Version 10.6.8 (1898) on Mac computer, will the same issue happen?
Microsoft Remote Desktop Beta for Version 10.6.8 (1898)
https://install.appcenter.ms/orgs/rdmacios-k2vy/apps/microsoft-remote-desktop-for-mac/distribution_groups/all-users-of-microsoft-remote-desktop-for-mac
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