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- Use a personal pool. Ref: https://learn.microsoft.com/en-us/azure/virtual-desktop/configure-host-pool-personal-desktop-assignment-type
- VM's need to be joined to either AD or AAD - they can not be in a workgroup. External users does not refer to AAD B2B. It’s the business relationship to the organization hosting AVD. The user objects still need to exist in AD > AAD off the hosting orgs directories.
Hope that helps.
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