Does your office have a rule about what staff can paste into AI, or is everyone winging it?
Microsoft's Copilot is a good example of why it matters. Same name, same look, but which account you sign in with changes who controls what you type.
What happened
Copilot is Microsoft's AI chat assistant. It's built into Windows, the Edge browser, a phone app, the copilot.com website and the Office apps. On August 18, 2026, Microsoft rolled out an updated Copilot app that lets you sign in with a personal Microsoft account, a work account, or both. Microsoft says the two stay separate. What you do on one doesn't flow to the other.
Microsoft's own privacy pages describe three different setups.
What this means in plain English
Personal account (the consumer version). This is Copilot signed in with a personal email like Outlook.com or Hotmail. For the older version of the app, Microsoft's privacy pages say it uses Copilot conversations for AI training by default for most users, unless you switch that off, and keeps conversation history for 18 months by default. For the updated app, Microsoft's page says prompts, responses and files "aren't used to train foundation models." Either way, those chats live in that person's own account. Your company's settings, record-keeping and IT oversight don't reach them.
Work account with free Copilot Chat. Sign in with your work Microsoft 365 account and Microsoft applies what it calls enterprise data protection. Its pages say prompts and responses, including any work content you paste in, aren't used to train the AI. Chats are logged, your IT admin can search and review them, and your company's settings and record-keeping rules apply.
Paid Microsoft 365 Copilot. This version goes further and draws on your organization's own data, like email and files, to answer questions. Microsoft says it only shows a person data they already have at least permission to view. Think of a very fast new assistant with a copy of every key that person already holds. It won't open locked doors. But it will find every door that was left unlocked, like that HR folder everyone can open and nobody remembers sharing.
None of these versions is always right. AI can be confidently wrong, so someone still has to check the answer.
Why a small business should care
Staff use AI because it's handy. If they're signed in with a personal account, your customer lists, pricing or employee details are sitting in a place your business doesn't control and can't review. That's a policy problem, not a technology problem, and it's cheap to fix.
Who's affected
Anyone at your business using Copilot on Windows, in Edge, on copilot.com, in the phone app or in Office
Especially anyone who has both a personal and a work Microsoft account on the same computer or phone
Businesses thinking about buying paid Microsoft 365 Copilot
What to do: everyone
Before using Copilot for work, check which account you're signed in with. Click your profile picture. It should be your work email.
Don't paste customer details, staff information, passwords or financials into AI on a personal account.
If you use Copilot on a personal account at home, look through its Privacy settings and decide what you're comfortable with.
Check AI answers before you send them to a customer or act on them.
What to do: if you run the business
Write a one-page rule: which AI tools are allowed, which account to use, and what never gets pasted in.
Have staff use their work account for work AI, so your company's protections apply.
Before buying paid Microsoft 365 Copilot, clean up who can open what. It will surface anything a person already has access to.
Decide how long you want Copilot chats kept, and have your IT provider set that up.
Questions to ask your IT provider
Are our staff using Copilot with work accounts, and can we steer them away from personal ones?
Who in our company can open folders they shouldn't?
If we buy paid Copilot, what needs tidying up first?
How long are our Copilot chats kept, and who can review them?
Sources
Microsoft Support: Privacy FAQ for Microsoft Copilot
Microsoft Support: Microsoft Copilot for individuals: your activity history
Microsoft Support: Data protection when using Microsoft Copilot Chat for work or school
Microsoft Learn: Data, Privacy, and Security for Microsoft Copilot
Contact Nautalex to see how we can help you with using AI safely at work.
