Will Setting LegacyAuthProtocolsEnabled To False Also Stop Azure ACS?

Jamie Brandwood 131 Reputation points
2024-09-25T18:30:59.05+00:00

When setting -LegacyAuthProtocolsEnabled to False w/ Set-SPOTenant, would this also impact Apps / Add-Ins using Azure ACS for integration to SharePoint Online?

I know Azure ACS integration w/ SharePoint Online can be managed with -DisableCustomAppAuthentication but wanted to check if it classes CustomAppAuthentication as LegacyAuth and therefor would be blocked by the change to -LegacyAuthProtocolsEnabled?

My expectation for -LegacyAuthProtocolsEnabled was this only impacts anything using BasicAuth ... Is that correct or does LegacyAuth encompass more than just BasicAuth?

SharePoint Development
SharePoint Development
SharePoint: A group of Microsoft Products and technologies used for sharing and managing content, knowledge, and applications.Development: The process of researching, productizing, and refining new or existing technologies.
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  1. Ling Zhou_MSFT 17,060 Reputation points Microsoft Vendor
    2024-09-26T06:26:52.1166667+00:00

    Hi @Jamie Brandwood,

    Thank you for posting in this community.

    Setting the LegacyAuthProtocolsEnabled to False with Set-SPOTenant will not impact apps or add-ins using Azure ACS for integration with SharePoint Online.

    The LegacyAuthProtocolsEnabled property in SharePoint Online determines whether legacy authentication protocols are allowed. Legacy authentication refers to older methods of authentication, such as basic authentication.

    The DisableCustomAppAuthentication property in SharePoint Online controls whether custom app authentication using Azure Access Control Service (ACS) app-only access tokens is allowed.


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