Welcome to the Microsoft Q&A Platform! Thank you for asking your question here.
We understand from your query that you are experiencing an issue while trying to use Windows App on MAC Book and sorry for the inconvenience caused.
Ensure that you have a stable and working internet connection. You can try accessing other websites or online services to verify your connectivity.
Most networks don't block access to the internet, but if your network does, you need to allow access to the list at Required FQDNs and endpoints for Azure Virtual Desktop.
Note: Please ensure the device is running macOS 12.0 or later.
Please also note that the latest version is available on Windows app.
General availability 11.0.3
Users: Download Windows App from the Mac App Store. To learn more, see Get started with Windows App.
Administrators: you can download Windows App outside of the Mac App Store as a .pkg file from https://go.microsoft.com/fwlink/?linkid=868963.
Try using a different network connection. If you are using a Wi-Fi connection, try using a wired connection instead. If you are using a wired connection, try using a different Wi-Fi network.
Ensure that the firewall settings on your Macbook and the remote PC are not blocking the connection. You can try temporarily disabling the firewall to see if it resolves the issue.
Please refer to this for more information Get started with Windows App to connect to desktops and apps
If you have any further queries, do let us know.
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