Exchange Online error: Write-ErrorMessage : Object reference not set to an instance of an object.

[Edwin_Oroko]

I am unable to Modify ab Authentication Policy : Set-AuthenticationPolicy -Identity "Block Basic Auth" -AllowBasicAuthImap:$false

I get the below error: 

Write-ErrorMessage : Object reference not set to an instance of an object.

When apply the Authentication Policy to a user using Set-CASMailbox it does not change anything. Kindly help. Thank you.

[#2]

I have the same error message when trying to run this command. I tried also Cloud Shell/ PowerShell from Azure portal and here I got the same error: "Set-AuthenticationPolicy: Object reference not set to an instance of an object."

[#3 · Accepted solution]

@Edwin_Oroko 

For me the solution was creation of new policy with all the desired parameters in one command. It is strange, but it is working :)

Try to run the following command.:

New-AuthenticationPolicy -Identity "Block Basic Auth_v2" -AllowBasicAuthPop:$false -AllowBasicAuthSmtp:$false

Do not forget to put all the parameters to command. Edit of policy via Set-AuthenticationPolicy  is (currently) not working. You cannot edit it later.

[#4]

@matacek Thank you! Yes, seems one cannot edit it later.