Thanks for posting your question in the Microsoft Q&A forum.
Here are the steps you can try:
- Ensure that the Azure AD user accounts have the required permissions to log in to the AVD session host.
- Confirm that the AVD session host is properly Azure AD joined by checking the "Azure AD joined" status in the Azure portal. if the session host is not Azure AD joined, you may need to re-join it to Azure AD.
- Check if the Azure AD user accounts are configured for password-based sign-in. ensure that the users know the correct password for their Azure AD accounts.
- On the client machine, clear the Remote Desktop client cache by deleting the contents of the "%AppData%\Microsoft\Credentials" folder.
- Review any conditional access policies configured in Azure AD that might be blocking the user sign-in. ensure that the policies are not preventing access from the AVD session host or the user's location.
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