Error Message When Attempting to Allow Legacy Exchange Tokens in Exchange Online

Question

I am attempting to allow legacy exchange tokens because an Outlook plug-in requires it. I am following the instructions outlined here: https://learn.microsoft.com/en-us/office/dev/add-ins/outlook/turn-exchange-tokens-on-off

After connecting to Exchange Online Management via PowerShell and running the command:

Set-AuthenticationPolicy AllowLegacyExchangeTokens -Identity "LegacyExchangeTokens"

I receive the following error:

Set-AuthenticationPolicy : A positional parameter cannot be found that accepts argument >'AllowLegacyExchangeTokens'. At line:1 char:1

• Set-AuthenticationPolicy AllowLegacyExchangeTokens -Identity "LegacyE ...
• CategoryInfo : InvalidArgument: (:) [Set-AuthenticationPolicy], >ParameterBindingException
  • FullyQualifiedErrorId : PositionalParameterNotFound,Set-AuthenticationPolicy

How can I allow legacy tokens if it will not let me?

Thank you!

Answer 1

Hello, @Sam Bennett

Welcome to the Microsoft Q&A platform!

According to the error message, there is an issue with your parameter. Please check it carefully in order not to miss any key point like "-".

After finishing this adjustment, you may run the cmdlet successfully.

Should you need more help on this, you can feel free to post back. 

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If the answer is helpful, please click on “Accept answer” as it could help other members of the Microsoft Q&A community who have similar questions and are looking for solutions.

Thank you for your support and understanding.

Best Wishes,

Alex Zhang

Answer 2

Can confirm - the command to enable legacy tokens is given correctly on the page OP referenced, but if you copy that command and paste it into PowerShell it drops the hyphen before the AllowLegacyExchangeTokens parameter. I didn't spot it until I read this article.

Thanks!