HOW TO ENABLE LEGACY EXCHANGE TOKENS IN EXCHANGE ONLINE

To successfully enable Legacy Exchange Tokens, the following conditions must be met:

You must be a member of the Exchange Administrator role group.
The procedure must be executed from Windows PowerShell on a local machine. This cannot be performed using the Exchange Online cloud module console.

If the module is not currently installed on your system, install it using the following command:

Install-Module -Name ExchangeOnlineManagement

Note:

If prompted to install the NuGet provider, enter Y to proceed.

If prompted to trust the PSGallery repository, enter A to confirm.

Once the module is installed, import it and initiate a connection to your Exchange Online environment:

Import-Module -Name ExchangeOnlineManagement
Connect-ExchangeOnline

Use the following command to enable legacy token usage globally:

Set-AuthenticationPolicy -AllowLegacyExchangeTokens -Identity "LegacyExchangeTokens"

To verify that Legacy Exchange Tokens have been enabled, run:

Get-AuthenticationPolicy -AllowLegacyExchangeToken

Expected Output:

AllowLegacyExchangeTokens : True

Module Import Error: Ensure that you are using local PowerShell and have administrative privileges.
Missing Output: Use the -AllowLegacyExchangeToken switch explicitly in the Get-AuthenticationPolicy command.
Environment Note: Restart your PowerShell session after installing the module to ensure proper recognition.

EXAMPLE PROCEDURE