Microsoft is retiring classic SharePoint pages and custom scripting in SharePoint Online, in two phases starting March 1, 2027.
Because ShareGate Migrate copies content by recreating it at the destination, these changes can prevent some classic content from migrating as-is once the applicable phase takes effect for your tenant.
This article explains these changes, how they affect your migrations, and how you can prepare for them.
What's changing
Microsoft is rolling out these changes to reduce the security and governance risks associated with legacy customization models and to move organizations toward the modern SharePoint experience.
For full details, see Microsoft's official announcement: Deprecation of classic SharePoint pages.
Phase | Starts | What changes |
Phase 1 | March 1, 2027 | For all tenants, the creation of new classic publishing sites is disabled. For tenants created on or after this date, classic pages become read-only, and custom scripting is turned off by default and can't be re-enabled. |
Phase 2 | October 1, 2028 | The Phase 1 restrictions on classic pages and custom scripting extend to all remaining tenants. |
Note: Existing classic pages aren't deleted or changed. They remain viewable, but become read-only once the applicable phase takes effect for your tenant.
How does this affect your migrations?
ShareGate Migrate migrates classic pages and custom-scripted content, such as web parts and ASPX pages, by recreating them at the destination.
Once the applicable phase takes effect for a destination tenant, Microsoft no longer allows this content to be created there, and ShareGate Migrate can't work around that restriction.
This affects the following classic content:
Wiki pages
Web part pages
Blog pages
Publishing pages
Custom ASPX pages created with SharePoint Designer or a third-party tool
Note: If your destination tenant is created on or after March 1, 2027, this content can't be migrated as classic content from day one.
What's not affected
These changes don't affect:
Classic team sites
Classic list and library views, and list form pages.
Custom scripts embedded in these are still subject to the scripting restrictions.
What you can do now
As you plan migrations involving classic content, consider the following:
Assess your source environment now. Microsoft's open source 365 Assessment Tool can help you identify classic pages, web parts, and customization patterns before you migrate.
Prioritize high-traffic or business-critical pages first, and modernize them before migrating to a tenant where the restrictions already apply.
If you're migrating into a newly created tenant, plan to modernize classic content beforehand. A tenant created on or after March 1, 2027, won't accept it as classic.
Note: Microsoft recommends using its PnP modernization tooling to transform classic pages.
Evaluate it carefully: the PnP Framework is scheduled for public archive in Q2 2027, doesn't carry a Microsoft support SLA, and doesn't currently support all web part types, including ListFormWebPart.
Troubleshooting custom script errors in the meantime
Some destinations may already show a warning that custom scripting is disabled.
If you see a warning or any of the related errors, see the related article below: