As many organisations already know, Microsoft has been gradually phasing out the SharePoint Add-In model, encouraging customers to move to solutions built on the SharePoint Framework (SPFx) for modern SharePoint environments.

For customers using Sintel Forms, this transition has already been underway for some time. Sintel Forms was originally built on the SharePoint Add-In model and has now been replaced by Sintel Apps, our new solution built on the SharePoint Framework.

Many customers have already completed the move to Sintel Apps, but if your organisation is still running Sintel Forms, now is a good time to ensure you have a plan in place.

Key Date to Keep in Mind

To continue using your forms without disruption, Sintel Forms should be upgraded to Sintel Apps before April 2nd, 2026.

If you haven’t already completed the migration, we recommend reviewing your existing forms and scheduling the upgrade in advance of this date.

What the Upgrade Involves

The process involves installing Sintel Apps and upgrading existing forms using the built-in upgrade wizard.

The upgrade has been designed to minimise disruption:

• SharePoint lists remain unchanged

• Existing form data is preserved

• Forms are rebuilt in the new designer as a preview

• Nothing changes for users until the upgraded form is saved

This allows administrators and form owners to review the new version before making it live.

For IT and SharePoint Administrators

The first step is installing the Sintel Apps solution in your Microsoft 365 tenant.

Once installed, existing forms can be upgraded using the upgrade wizard within Sintel Apps.

Step-by-step guidance is available through:

• The Sintel Forms → Sintel Apps upgrade guide

• The Sintel Apps knowledge base

   

A Good Time to Review All SharePoint Add-Ins

While upgrading Sintel Forms, it’s also worth reviewing any other SharePoint Add-Ins currently in use within your tenant.

Since Microsoft is moving away from the add-in model altogether, organisations should ensure they have a clear plan for migrating legacy add-ins to modern solutions built on the SharePoint Framework or other supported technologies.

Taking this opportunity to review your existing add-ins can help avoid future disruption as the platform continues to evolve.

Need Assistance?

If you have questions about upgrading your forms or would like assistance with the migration to Sintel Apps, our team is happy to help.