Public Preview: High Volume Email for Microsoft 365

Peter_Holdridge thanks, i was cuing off the linked documents that said that was deprecated (I suspect i misunderstood what the doc was trying to say)

I now have PowerShell installed on my mac and the exchange PowerShell module installed (and of course none of the documentation was 100% accurate on that either).

I did the following:

New-AuthenticationPolicy -Name "Allow Basic SMTP Auth"

This worked ok and i saw the policy be generated

Set-User -Identity email address removed for privacy reasons -AuthenticationPolicy "Allow Basic SMTP Auth" (that is the identiy of the HVE account)

This worked OK with no errors or messages.

I then tried

Set-AuthenticationPolicy -Identity "Allow Basic SMTP Auth" -AllowBasicAuthSmtp                          

and got the following error

Set-AuthenticationPolicy: Object reference not set to an instance of an object.

I am at a loss on what to do next.  I am doing all of this because the app I use is telling me it can't auth (the app works find using the old endpoint) and a traditional O365 user.

5.7.139 Authentication unsuccessful, either user not found, locked or disabled. Contact your administrator. (500)

I note i can Get-AuthenticationPolicy for this policy just fine, its the set thats not working.  Am I supposed to use the internal complex HVE name - the one that is string of numbers @ localhost?