SharePoint Online Classic Deprecation Extension Instructions

How to Extend Support for SharePoint Online Classic Sites

The impacted templates include: 

• BLANKINTERNETCONTAINER#0
• CMSPUBLISHING#0
• BLANKINTERNET#0
• CSPCONTAINER#0

Technical Actions Required to Prevent Disruption

To set a feature flag that opts-out of the deprecation and ensures continued access to Classic SharePoint and the ability to create new publishing site collections, complete the following steps by September 15, 2025:

1. Delay Enforcement Tenant-Wide:

This command postpones script disablement until March 15, 2026, providing critical time for your organization and AppSpace to ensure all is prepared on your environment for this change.

Set-SPOTenant -DelayDenyAddAndCustomizePagesEnforcementOnClassicPublishingSites $true

2. Enable Custom Script for Specific Sites:

This command enables custom script for an intranet site collection.

Set-SPOSite <SiteURL> -DenyAddAndCustomizePages $false

3. Re-Enable Classic Publishing Site Creation :

This is needed for new classic publishing site collections or publishing features creation are still required after September 15, 2025.

Set-SPOTenant -AllowClassicPublishingSiteCreation $true

PowerShell Setup & Permissions

To execute the above scripts:

Required Module 

• The latest SharePoint Online Management Shell is installed (minimum version: 16.0.26211.12010 or higher). 
• You can check your version with: Get-Module -Name Microsoft.Online.SharePoint.PowerShell -ListAvailable
• Download link: Download Management Shell (Please verify the latest official Microsoft download link if this one is outdated).

Required Permissions

• The user executing these scripts must have the SharePoint Admin role in Microsoft 365 and the site collection admin (required for tenant-level settings like Set-SPOTenant).
• Connected Session: A properly connected session using:
• Connect-SPOService -Url https://<yourtenant>-admin.sharepoint.com
• (Replace <yourtenant> with your tenant name.)