Reenable the Relaying Party Suite (RPS) service for SharePoint Online

Microsoft plans to deprecate its Relaying Party Suite (RPS) service in SharePoint. While this doesn’t directly impact WebDAV, it affects how CDM Legacy (v2.22 or below) currently generates cookies for WebDAV’s authentication.

Microsoft is soft-disabling RPS before the end of August 2025. If you are on CDM Legacy (2.22 or below) and this happens, you can temporarily reenable RPS with PowerShell, and CDM 2.22 or below will continue working until RPS is permanently deprecated on October 15, 2025.

As a more permanent solution to the removal of RPS, we have released CDM Legacy (2.24), which uses a different method for generating cookies, and it works even when RPS is disabled on a tenancy. At the very least, we recommend that all CDM Legacy customers upgrade to 2.24 as soon as possible, and also start making plans to upgrade fully to CDM V3 (now in general availability).

Immediate fix

If you are on CDM Legacy (2.22 or below), you can temporarily reenable the RPS service for SharePoint Online by running a PowerShell script. You can download this file by clicking here.

Prerequisites:

  • Windows PowerShell 5.x

  • You must sign in with a SharePoint or Global Administrator account for your Microsoft 365 tenant.

The script updates your SharePoint Online tenant properties to revert Microsoft’s RPS deprecation. When you run the PowerShell script, you only need to enter your tenant name (for example, contoso), not the full admin URL. The script will automatically construct the full admin URL for you (https://contoso-admin.sharepoint.com). The PowerShell script targets two properties:

  • AllowLegacyBrowserAuthProtocolsEnabledSetting = $true: Enables your tenant to accept the rollback, but only takes effect if Microsoft has already applied RPS deprecation to your tenant.

  • LegacyAuthProtocolsEnabled = $true: Reverts the deprecation and will remain effective until October 15, 2025, when you must upgrade to CDM Legacy 2.24 or CDM v3.

This completes the process of temporarily reenabling RPS so that CDM Legacy (2.22 or below) can continue working until Microsoft permanently deprecates its RPS service in SharePoint on October 15, 2025.