For years, COM (Component Object Model) plug-ins have been the quiet workhorses behind legal IT systems. They’re the invisible connectors that make Outlook talk to your document management system, help you record time, or automatically file emails where they belong.
But from 2026, they’ll start to be no more.
Microsoft has confirmed that COM add-ins are being phased out. The new Outlook for Windows and other Office 365 applications simply won’t support them. For law firms still relying on these legacy tools - and that’s a lot of firms - this isn’t a small technical change. It’s a strategic wake-up call.
The SharePoint Add-In model is confirmed to retire in April 2026, and throughout the next 5 years, multiple add-ins will be discontinued. For further updates on Microsoft’s product end-of-support and retirement, please see here.
What Are COM Add-ins (and Why Do They Matter)?
Think of a COM add-in as a bridge. It lets Microsoft Office applications like Outlook or Word connect to other systems — perhaps a time recording platform, a case management tool, or a bespoke integration written years ago by someone who has since left the firm.
They’ve been invaluable for years. But they were designed for a different era - one where everything ran on Windows desktops, not in the cloud.
Now, as Microsoft shifts toward Office Web Add-ins (built with modern web technologies like JavaScript and HTML), COM plug-ins are being left behind. The new Outlook doesn’t support them at all.
The Hidden Risk: Do You Know What You’re Running?
Here’s the uncomfortable truth: many firms don’t actually know how many COM plug-ins they’re using or what business processes rely on them.
These tools often sit quietly in the background, woven deep into everyday workflows. When Microsoft finally removes support, some firms will only realise the problem when critical functions stop working.
To put it bluntly, some firms may be in the dark about just how exposed they are.
How to Tell If You’re Affected
Not sure whether your firm uses COM plug-ins? Here’s how to start checking:
What Comes Next
Microsoft’s replacement is the Office Web Add-in framework - cloud-based, secure, and cross-platform. It’s a step forward technologically, but here’s the catch: not every COM plug-in has a web version yet.
That means some firms will need to rebuild their critical tools from scratch. Others will need to migrate existing systems carefully to avoid breaking workflows or losing data.
How Xperate Can Help
At Xperate, we’ve already helped firms navigate this transition - building modern, web-based add-ins that replicate and improve on their existing workflows.
We’ve done it before. In fact, our Levi’s case study shows exactly how we helped a large, multi-departmental law firm modernise its Outlook integrations - making it faster, simpler, and ready for the future.
Our expertise covers:
We don’t just build software. We help firms to future-proof their digital foundations.
The Time to Act Is Now
2026 is only around the corner, but discovery, development, and deployment all take time. Don’t wait until your add-ins stop working - by then, you’ll be reacting under pressure.
If you’re unsure what COM plug-ins your firm depends on, or whether you’re at risk, get in touch with Xperate. We’ll review your setup, identify what needs attention, and map a clear, cost-effective route to modernisation.
To book a COM Add-in Audit and ensure your firm is ready for what’s next, please get in touch.
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