M365 Changelog: (Updated) Retirement of custom default result sources in Microsoft Search for modern search experiences

MC526131 – Updated March 16, 2023: Microsoft has updated the content for clarity. Thank you for your patience.

Classic SharePoint search supports the feature of result sources where you can define custom KQL filters on what items should be returned for your search result. This feature has been honored in Microsoft Search, but as the same result source is used across all verticals with SharePoint content it limits the flexibility and intention of the feature.

In November 2021 Microsoft shipped the capability for administrators to add KQL to the verticals in Microsoft Search. Vertical configuration succeeds the classic result source rewrite capability and allows for greater flexibility per vertical, and the change reflects what has been documented in Differences between the classic and modern search experiences in SharePoint.

When this will happen:

Microsoft will be rolling out this change in mid-April 2023.

How this affects your organization:

Starting mid-April 2023, customers using a custom default result source for KQL rewrite of the modern search experience should move KQL rewrites from those sources over to the vertical administration configuration.

What you can do to prepare:

If your organization is utilizing a custom default result source for KQL rewrites of the modern search experience, you should move KQL rewrites to the vertical administration configuration.

Note: Query rules at site or hub site scoped searches with promoted results are not affected as promoted results are returned in the modern search experience for sites regardless of the result source. See Manage query rules for more information on query rule behavior. Classic search experiences and experiences built on the SharePoint search API’s are not affected by the retirement.

Additional information