TL;DR
- If Copilot sounds confident but wrong, it’s usually a data foundations issue, not an AI problem.
- Messy, duplicated, or unclear content leads Copilot to fill in the gaps.
- Fixing structure, metadata, permissions, and prompts makes Copilot far more reliable. And improves everyday work too.
Dear WebVine,
We’ve got a bit of a trust issue brewing.
Our team has been using Microsoft Copilot and (on the surface) it looks brilliant. The answers are confident. Well‑written. Very convincing.
But then we dig a little deeper. We click through to the files it references. We try to validate the facts.
And… the information isn’t quite right.
Some of the data it seems to be pulling from our documents doesn’t exist. Some conclusions don’t line up with what’s actually in SharePoint.
We’ve realised what’s happening: Copilot is hallucinating.
Why is this happening? And more importantly, how do we fix it?
Chloe’s Take
Dear Slightly Spooked,
First up: you’re not alone. Not even a little bit.
We hear this all the time. From councils, healthcare providers, professional services teams, not-for-profits… pretty much anyone excited about Copilot and then has that moment of, “Hang on… where did it get that from?”
Here’s the reassuring part: in most cases, Copilot isn’t being reckless or broken. It’s doing exactly what it’s designed to do. Making sense of the information it can see.
The less reassuring (but fixable) part?
If your data is messy, outdated, duplicated, poorly labelled, or inconsistently structured… Copilot will confidently stitch together messy answers.
Think of Copilot like a very fast, very enthusiastic librarian. If the books are misfiled, unlabelled, and half of them are outdated, don’t be surprised if you get the wrong recommendation.
In short:
Messy data in = messy AI answers out.
Let’s talk about how to fix it.
Why Copilot Hallucinates (Even in Microsoft 365)
Copilot works by:
- Looking at the content it has permission to access
- Trying to infer meaning, patterns, and context
- Generating the most likely helpful response
When your environment includes:
- Multiple versions of the same document
- Deep, inconsistent folder structures
- Files with vague names like Final_v7_REALLYFINAL.docx
- Missing or meaningless metadata
- Permissions that don’t reflect reality
Copilot fills in the gaps.
Not maliciously. Not carelessly.
It’s more like a confident intern who’s been told, “Just do your best with what you’ve got.”
6 Practical Steps to Reduce Copilot Hallucinations
The good news? You don’t need to “turn off AI” or panic‑ban Copilot. You need to tidy up the foundations it relies on.
1. Clean Up Obvious Content Clutter
Start with the low‑hanging fruit:
- Archive or delete outdated documents
- Remove duplicate files
- Agree on what the source of truth is
If humans struggle to find the right version, Copilot definitely will too.
2. Simplify Your Structure (Less Is More)
Deep folder mazes might feel organised (and old style). But they confuse both people and AI.
Aim for:
- Flatter structures
- Clear site and library purposes
- Consistent naming conventions
If you have to explain your folder logic in a meeting… it’s probably too complex.
3. Use Metadata Like Labels on a Filing Cabinet
Metadata gives Copilot context. Something folders alone can’t do.
Even a small set of meaningful tags (document type, business area, status) can dramatically improve answer quality.
Think of metadata as the difference between: “Here’s a pile of paper” and “Here are clearly labelled folders.”
4. Fix Permissions (They Matter More Than You Think)
Copilot can only work with what it’s allowed to see, but it may generate confident summaries based on incomplete retrieval context..
That’s how you end up with:
- Incomplete answers
- Missing nuance
- Over‑confident summaries
Permissions hygiene = better AI answers.
The Takeaway
If Copilot is hallucinating in your environment, it’s rarely a Copilot problem.
It’s a data quality, structure, and governance problem. One that many organisations are only now discovering because AI is shining a very bright light on it.
The upside? Fixing this doesn’t just improve Copilot. It improves search, collaboration, onboarding, and day‑to‑day work for your people.
And if you need a hand getting your data (and Copilot) back on solid ground - well, you know where to find us.
About Chloe:
Chloe Dervin is WebVine’s Managing Director and resident intranet whisperer.
With a background in digital strategy and a knack for translating tech into plain English, Chloe helps organisations untangle their messiest SharePoint setups and turn them into something people want to use.
She’s worked with everyone from local councils to fast-growing engineering firms, and she’s seen it all. From “Final_v2_REAL_final.docx” nightmares to intranets that haven’t been touched since 2011.
Her superpower? Making the complex feel doable, and helping teams move from “we’re flying blind” to “we’ve got this.”
When she’s not rewriting the rules of digital workplaces or penning her latest “Dear WebVine,” Chloe is making work, work for everyone.
FAQs
What does it mean when Copilot is “hallucinating”?
Hallucination is when Copilot generates information that sounds plausible but isn’t actually supported by the content in your Microsoft 365 environment. It’s not lying. It’s filling in gaps based on incomplete or messy data.
Is Copilot broken if it gives incorrect answers?
In most cases, no. Copilot is behaving exactly as designed. It’s trying to infer meaning from the information it has access to. When that information is outdated, duplicated, or poorly structured, the output reflects that.
What are the most common causes of Copilot hallucinations?
Common causes include multiple versions of documents, deep and inconsistent folder structures, vague file names, missing metadata, and permissions that don’t reflect how people work.
Do we need to stop using Copilot until this is fixed?
No. The recommendation is not to panic or disable Copilot, but to clean up the foundations it relies on. Improving data quality reduces hallucinations and improves Copilot’s usefulness over time.
How much metadata do we actually need?
You don’t need a complex taxonomy to see improvements. Even a small, meaningful set of metadata, like document type, business area, or status, can significantly improve Copilot’s understanding and responses.
Why do permissions affect Copilot’s answers?
Copilot can only summarise what it’s allowed to see. If permissions are inconsistent or overly restrictive, Copilot may generate confident summaries based on partial information, leading to missing nuance or incomplete answers.
Can better prompts really make a difference?
Yes. Vague prompts encourage Copilot to guess. Being explicit about which document, library, or time period you’re referring to reduces ambiguity and improves accuracy.
Should Copilot ever be used without human review?
No. Copilot is best treated as a highly confident first draft. Facts should always be sense‑checked, citations followed back to source documents, and outputs reviewed before anything is shared externally.
Sources
- WebVine – Understanding AI hallucinations and how to avoid them
https://webvine.com.au/understanding-ai-hallucinations-and-how-to-avoid-them/ - Microsoft Learn – Microsoft Copilot for Microsoft 365 overview
https://learn.microsoft.com/en-us/copilot/microsoft-365/overview - Microsoft Learn – Data, security, and permissions in Copilot
https://learn.microsoft.com/en-us/copilot/microsoft-365/data-privacy-security - Microsoft Learn – SharePoint information architecture guidance
https://learn.microsoft.com/en-us/sharepoint/information-architecture-modern-experience