Most of the SharePoint environments we look after have a few skeletons in the cupboard. An intranet home page someone built back in 2014. A wiki that one team used for six months and then forgot about. A page with a bit of custom script on it that a contractor added years ago, and nobody now dares to touch.
Well, Microsoft has decided it’s time to tidy those up. They’ve announced that Classic SharePoint pages, Classic Publishing sites and custom scripting are all being retired from SharePoint in Microsoft 365. There’s a clear timeline, it’s not urgent today, but it IS coming, and it’s much easier to deal with on your own terms than in a rush at the last minute.
What’s going away?
- Classic Publishing sites. You won’t be able to create new ones, or switch the classic publishing feature on for new sites.
- Custom scripts. Adding or editing custom script on a site will be turned off by default.
- Classic pages people have built. That covers wiki pages, web part pages, blog pages, publishing pages and custom ASPX pages (the kind built in SharePoint Designer or by a third party). These become read-only. You’ll still be able to see them, but not edit them or make new ones.
The good news is that nothing is being deleted. Your content stays exactly where it is. Lists, libraries and list forms aren’t affected either.
When does it happen?
1 March 2027: new Microsoft 365 tenants can’t create classic pages or run custom scripts at all, and nobody can create new classic publishing sites.
1 October 2028: this is the date that matters for existing businesses. Classic pages go read-only, custom scripts are switched off, and the setting that used to let you override that is locked.
That might sound like plenty of time (and it is, if you start now). But in our experience “classic SharePoint” is rarely one thing. It’s years of sites, pages and little customisations built by different teams, and nobody has a full list.
How do you find out what you’ve got?
Microsoft has a free Microsoft 365 Assessment Tool that scans your whole tenant. It finds your classic pages, the web parts on them and any customisations, and it gives you a sense of how hard each one will be to modernise. It even links to Microsoft’s guidance for each type of problem it finds.
We’ve run it ourselves, and it’s genuinely useful. Some of what it finds is easy to fix: Microsoft and the PnP community have PowerShell scripts that can convert a lot of classic pages to modern ones automatically. Some of it is not so easy. Heavily customised pages, custom scripts and anything built with a design tool years ago usually need a person to look at them and decide whether to rebuild or retire. There’s also a newer open-source tool, the SharePoint Page Migration Agent, aimed at the tricky cases, but it’s still in preview and Microsoft doesn’t support it.
What we’d do now
- Run the assessment first. You can’t plan for what you haven’t found.
- Sort the list by what matters. Pages people use every day, and anything business-critical, go to the top. That forgotten wiki from 2016 goes to the bottom (or straight in the bin).
- Move in small batches. Check the content, links, permissions and layout after each batch before you move on.
The simple stuff you can probably handle yourselves. For the complicated stuff, it’s worth having someone who’s done it before check your plan, because that’s exactly where the automated scripts run out of road.
Want us to take a look?
Microsoft 365 is what we do every day. We’re happy to run the assessment for you, tell you honestly what’s easy and what isn’t, and help you plan the move well before October 2028 forces the issue.
Book a free health check or give us a call on 0800 688 768.