Copilot in Outlook drafts, summarizes and ranks. It does all of that inside a fence Microsoft has published, so you can see the edges before you buy. Copilot works in one mailbox, and that mailbox is yours. Several whole categories of message sit outside it. The ranking starts the day you switch it on and runs forward from there. And it needs a separate per-person license on top of the Microsoft 365 subscription you already pay for.
That fence is mostly documented, which is unusual and useful. Almost everything below comes from Microsoft’s own support and admin pages, rather than from anybody’s opinion of the output. The surprises are about which mail Copilot is allowed to look at, rather than about the quality of what it writes.
- One mailbox, and it has to be yours. Microsoft states that Copilot scenarios in Outlook “are not available on a user’s archive mailbox, group mailboxes, or shared and delegate mailboxes that they have access to”. A firm address several people work is outside the fence entirely.
- The ranking only ever looks forward. Copilot “doesn’t prioritize older, existing messages”, and when you change the criteria it “does not go back and re-evaluate or change the priorities of mail you’ve already received”. The backlog you wanted help with stays exactly as it is.
- Anything a rule already filed is invisible to it. Microsoft’s own exclusion list opens with mail “delivered to a folder other than your Inbox”, then runs to eight more categories.
- Encrypted and rights-protected mail is out of reach. That’s by design rather than by defect, and it matters most to the firms most careful about it.
- It waits to be asked. Summarize is a button on a thread you already chose to open. The priority tag is the exception, and what it produces is a label and a sentence of reasoning, with the acting left to you.
What a Copilot license actually buys
Two different products share the name. Telling them apart is the first decision you make, rather than a footnote to it.
Copilot Chat comes with the subscription. Microsoft’s own pricing page states that “Microsoft 365 Copilot Chat is available at no additional cost for all Microsoft Entra account users with an eligible Microsoft 365 subscription” (checked September 6, 2026). Inside Outlook, Microsoft describes what that buys as the ability to “ask questions about your inbox, calendar, meetings and other limited data and take action directly in Outlook”. The phrase doing the work there is “other limited data”. The free tier answers about the mailbox and the calendar. The paid one reaches across your files, your chats and the rest of the organization’s content.
Microsoft 365 Copilot is the paid add-on. Microsoft’s licensing documentation is explicit that it “is available as an add-on plan with one of the licensing prerequisites listed in this article”. The pricing page lists it at “$30.00 user/month, paid yearly” on an annual commitment, and adds that “a separate license for a qualifying Microsoft 365 plan is required” (both checked September 6, 2026). That’s a second per-person subscription stacked on the first. It’s also what carries the features most people mean when they say Copilot in Outlook. Microsoft’s frequently asked questions page for Copilot in Outlook records a last updated date of February 2026, and notes plainly that the described feature set “is available to customers with a Microsoft Copilot (work) license”.
Two things follow, and both are worth knowing before a budget conversation. The first is how you start. Asked directly whether a trial exists, Microsoft’s answer is “No, there is no trial available for Microsoft 365 Copilot”, with the free chat tier offered in its place. The second is the plan underneath. It’s an add-on to a list of qualifying plans, so a firm sitting on a plan outside that list is buying a plan change before it buys anything else.
One more licensing edge catches shared machines. Microsoft states that “Copilot isn’t available when using device-based licensing for Microsoft 365 Apps for enterprise” (checked September 6, 2026). An office where Office is licensed to the workstation rather than the person stays outside it, whatever else has been bought.
Why the Copilot button is not there
The commonest question about Copilot in Outlook is where the button went. Five documented answers cover it, and only the last one is a fault.
The license is unassigned, or it’s the wrong one. As the section above says, the chat tier and the add-on are different entitlements with different surfaces.
You’re in a client that stops short of it. Microsoft states that “chatting with Copilot in Outlook is only available if you’re using a work or school account and you’re using new Outlook for Windows or Outlook on the web” (checked September 6, 2026). Summarizing and drafting reach further, into classic Outlook and Outlook for Mac. Chat stays in the two clients named there.
You’re on an older Outlook for Mac. Microsoft’s note is short: “Microsoft Copilot in Outlook is only available in the latest version of Outlook for Mac. Legacy Outlook isn’t supported.”
The mailbox sits on-premises. The next section covers it, and it produces a particularly confusing symptom: a Copilot icon that’s there and stays shut.
And the live defect, which is real and current. Microsoft has an open known issue, last updated August 5, 2026 and carrying a status of investigating. It describes that “after classic Outlook for Windows updates to build 20026.20182 and higher, you no longer have Copilot Chat or Copilot entry points in Outlook”, and that this “happens if you have a Copilot Chat (Basic) license or a paid M365 Copilot (Premium) account”. The listed symptoms include the button missing above the ribbon, the icon missing from the app bar, and Copilot appearing in Add Apps while selecting Open does nothing. Microsoft’s stated workaround is to “use new Outlook or Outlook Web Access (OWA)”. The page records that new profiles, cache clearing and re-signing in have all been tried, and that the button comes back inconsistently. If your Copilot vanished from classic Outlook this summer, you’ve been looking at a Microsoft bug rather than at your own machine.
One more, smaller than the others. Microsoft notes of the priority feature that “if you don’t see the Prioritize option, try again in a few days”, because “this feature is being rolled out gradually”. A colleague having something you’re still waiting for is normal here rather than diagnostic.
The single mailbox it works in
This is the limit with the largest practical reach for a small firm. Microsoft states it in one paragraph on its own page.
“Copilot scenarios in Outlook are only available on a user’s primary mailbox. They are not available on a user’s archive mailbox, group mailboxes, or shared and delegate mailboxes that they have access to. Copilot scenarios are not supported on mailboxes that are not hosted on Exchange Online” (checked September 6, 2026). Microsoft’s admin requirements page repeats it as a formal requirement rather than a caveat.
Read that against how professional practices actually arrange their email, and four separate gaps open up.
The firm address. The info@, admin@ or accounts@ that two or three people work through the day is a shared mailbox. Microsoft names shared mailboxes in the exclusion, so whatever you’ve bought stays with your own inbox. If most of the pressure in your week arrives at an address that belongs to the business rather than to you, the shape of that problem and the tools built for it are alternatives to a shared inbox tool.
Delegate access. An assistant or a partner reading somebody else’s mailbox is in the same position. The Copilot license is assigned to a person, and it follows that person’s own mailbox. The mailboxes they’ve been given rights over stay outside it.
The archive mailbox. Online archives are where firms park the older half of their correspondence, which is precisely the half you remember too vaguely to search by keyword. It sits outside the fence too.
A mailbox that lives outside Exchange Online. Microsoft’s guidance for hybrid deployments is unambiguous: “Microsoft Copilot is cloud-based and has no access to on-premises mailboxes”. Grounding Copilot in mailbox content is unsupported where the primary mailbox sits on-premises (checked September 6, 2026). The symptom is the confusing one mentioned above. Microsoft’s own compatibility table covers a user of Outlook in Microsoft 365 Apps with an on-premises mailbox and both licenses assigned. It gives the expected result as “Copilot icon exists but is dimmed / grayed-out and no UX can be called”. You’ve paid for it, you can see it, and it stays shut.
The messages it never looks at
Two separate exclusion lists apply. The second runs longer than most people expect.
The first is about protected mail. Microsoft states that “Copilot in Outlook can’t access S/MIME or Double Key Encryption encrypted emails”, and that its Outlook features “are not supported on signed or encrypted emails, on emails with IRM, or on some MIP labeled emails” (checked September 6, 2026). That’s the encryption doing its job. An assistant that could read a Double Key Encrypted message would be an argument against the encryption. It’s worth planning around all the same, because the pattern it creates runs backwards from what a firm would choose. The messages you took the trouble to protect are the messages your assistant is blindest to.
The second list governs the priority tagging, and it’s the one that quietly decides how much of your inbox is being judged at all. In Microsoft’s words, “the system doesn’t evaluate email delivered to a folder other than your Inbox (e.g., if you have a rule to send some mail to a subfolder)”. The list continues from there. Mail the sender marked low importance is out, and so is out-of-office mail. So is meeting mail, such as invites and declines and proposed new times. So is mail you send only to yourself, along with “mail with very little content”. Non-delivery receipts, quarantine messages, and encrypted messages whose content cannot be seen close the list (checked September 6, 2026).
That first clause is the expensive one, and it punishes good habits. You spend a couple of years building a sensible folder tree and a set of rules to fill it. Those rules move mail out of the Inbox, and the ranking judges what’s left. The better your filing, the smaller the slice Copilot is looking at. For the rule side of that trade, which folders earn their place and what a rule can be trusted to do on arrival, this collection has how to organize Outlook folders, and rules that fill them.
The others matter less one by one, and they add up. Meeting traffic is excluded, so the invitation that moves Thursday goes unranked. Thin messages are excluded, and “can you send that over today” is a thin message.
A ranking that only looks forward
Microsoft’s description of what the priority feature does is short and worth taking literally. Copilot “reviews your emails as they arrive in your inbox and assigns a priority (high, low, normal)”, using factors that include the people on the thread, their job titles and the content of the message. Your mail keeps arriving at its usual speed while that happens: “your emails will never be delayed as this process happens in parallel with mail delivery” (checked September 6, 2026). High priority shows as an up arrow in the message list. The low priority marker “is off by default”. Selecting a message shows a few lines explaining why Copilot thought it mattered.
Then come the two sentences that decide how useful this is in practice. They say the same thing twice, from different directions.
“Copilot will prioritize emails which are received after the feature has been turned on; it doesn’t prioritize older, existing messages.”
“Any changes you make will be applied to email you receive in the future. Copilot does not go back and re-evaluate or change the priorities of mail you’ve already received.”
The first of those means the ranking begins with tomorrow. The backlog that sent you looking for help in the first place stays as it is, and whatever relief arrives, arrives on tomorrow’s mail. The second means every refinement you make is a bet placed on correspondence somebody has yet to write. The week you just had is the one week you can’t test it against. If you realize in October that a particular client should always have been high priority, October is where that starts.
There’s a familiar shape here. Outlook’s older opinion about your mail is the Focused and Other split. It also stores your corrections permanently, and it also applies them only going forward, although it keys them to the sender’s address rather than to a written instruction. That mechanism, its overrides and the reasons a mailbox can look different on every device are where Focused Inbox falls short. The two systems are separate, and both can run at once. That’s worth knowing when you’re working out which of them moved something.
Last thing on the tag. What it produces is a marker and a short explanation. The filing, the scheduling and the writing down of a commitment all stay with you, and the message list keeps the order the mail arrived in until you sort or filter it yourself. Somebody still has to tell an important message from one that’s merely due soon, and that job is worked through in important versus urgent.
Waiting to be asked
The single most useful thing to understand about Copilot in Outlook is when it runs.
A summary happens when you press Summary by Copilot at the top of a thread. Coaching happens on a draft you’ve already written. A generated draft happens after you’ve opened a new message and typed a prompt. Chat happens in a pane you’ve opened, in answer to a question you’ve composed. Every one of those is triggered by you, on an item you’d already decided to deal with.
That’s a perfectly reasonable design, and for a genuinely long thread the summary is genuinely good. It’s simply a different job from the one most people are hoping to hand over. Copilot makes each individual message cheaper to read once you’re already reading it. Which messages to read, in what order, and what you owe as a result all stay your work. Twelve summaries is twelve times you chose a thread, waited, and read.
The priority tag is the one thing that runs unprompted, and the two sections above are the list of what it skips: the backlog, anything a rule filed, meeting mail, thin messages, protected mail.
The chat side carries a specific limit of its own. Microsoft states that “you can use Copilot chat in Outlook to schedule meetings with up to two other people, or add other events, like focus time, to your calendar” (checked September 6, 2026). Two other people is a small meeting. Anything larger stays the email chain it always was, and so does anything involving somebody outside the business whose calendar Microsoft can’t see.
Meeting preparation carries its own honest warning. Microsoft says that in meetings with no related content shared, “the Prepare feature may not produce a comprehensive summary and may respond with generic responses”. A first conversation with a new client is exactly a meeting with no shared history. It’s also exactly the one you’d most want prepared.
Your voice is a paragraph you have to write
People expect an assistant living in their sent items to learn how they write. Here, the voice is something you write down.
Copilot’s drafts can be steered by tone and length controls, and beyond that by custom instructions, which Microsoft describes as a prompt you compose explaining how drafts should be written. Its own worked example is “Keep emails short and direct, with bullet points where they make sense. Use a friendly tone and sign emails with my first name.” Microsoft states that the feature needs “a Microsoft Copilot (work) license or a Microsoft Copilot Pro (home) license” (checked September 6, 2026).
So your voice is a description you author and maintain. Years of your own sent mail stay out of it. The habits in there are yours to write down: that you open with something other than “I hope this finds you well”, that you answer the second question first, that this particular client gets two sentences and no preamble. When a draft comes out wrong, you edit your paragraph, and the next draft follows the edit.
Whether that matters depends on what you write. For internal notes, an instruction paragraph is plenty. For the sort of message a professional practice sends, where the tone is half the work, it’s a thin substitute for a habit.
Language is a related edge. Microsoft states that the priority feature “currently only supports Tier 1 languages”, with others to follow. Automatic language detection when summarizing “is currently available in Android, iOS, and Mac”, and is “coming to Windows and web in the future” (checked September 6, 2026). A practice with correspondence in a second language should test that before depending on it.
Spreadsheets, and the rest of the small print
A handful of narrower boundaries that only bite when they bite.
Attachments, and which kinds. Microsoft states that in new Outlook, where an email carries attachments, a file summary is offered for a PDF, PowerPoint or Word document (checked September 6, 2026). That list stops at three formats, and spreadsheets sit outside it. For an accounting or bookkeeping practice, the attachment that decides the reply is a workbook far more often than a slide deck, so that omission lands hard.
The message stays the unit. Summaries are of a thread. For a folder, a client relationship or a week, the route is asking chat a question and taking whatever it retrieves.
The reading features follow you. Beyond the priority exclusion, summarizing and drafting act on the item you have open, so the help tracks whatever is in front of you rather than the correspondence you filed away carefully. What each part of Outlook is actually for, and what a category can hold that a folder cannot, is organizing a busy Outlook inbox.
Marking a thing to come back to is still yours. Copilot chat flags messages when you ask. A flag is a date and a status, and that’s the whole of it. That’s a separate limit with its own consequences, set out in following up and flagging in Outlook.
Where your prompts and its answers end up
For a firm holding client financial information, this is the section that decides the rest. Microsoft’s position is documented and mostly reassuring, once you know all three parts of it.
Your mail stays out of the training data. Microsoft states that “prompts, responses, and data accessed through Microsoft Graph aren’t used to train foundation LLMs, including those used by Microsoft Copilot” (checked September 6, 2026). That’s worth having in writing, because it’s the first question every partner asks.
Copilot inherits your permissions, including your mistakes. Microsoft states that it “only surfaces organizational data to which individual users have at least view permissions”. The corollary is the part to act on. A document library somebody made broadly visible three years ago is now reachable by a tool that’s good at finding things. Copilot leaves access exactly where it was, and it makes loose access easier to trip over.
The conversations are kept, and the firm can read them. Microsoft states that “the stored data includes the user’s prompt and Copilot’s response, including citations to any information used to ground Copilot’s response”. Administrators can view and manage that data using Content search or Microsoft Purview, and retention policies can be applied to it (checked September 6, 2026). Users can delete their own Copilot activity history through the My Account portal. All of that is ordinary for a business system, and all of it is worth saying out loud before somebody pastes a client’s numbers into a prompt on the assumption it’s a scratchpad.
What is left once Copilot has answered
Set the limits side by side and a shape appears. Copilot sits beside a message you’ve already opened. It answers a question you’ve already asked, in the one mailbox that belongs to you, about mail that arrived after you started. What that leaves is everything that happens before the first message is open: deciding what today asks of you, in what order, and what it commits you to.
Point sits on the Microsoft 365 account you already run, mail and calendar both. You keep the address. You keep the history. Everything stays put, and a client reading your reply sees exactly what they always saw. What changes is where the deciding happens. Point reads each message for the request it contains, and for the date attached to that request. Each one is then weighed for importance and for urgency, and placed in an order before you open anything. The top of the feed is what the day actually owes, rather than what arrived most recently. Each thread carries a plain summary, which is enough to tell whether a fifty-message chain concerns you. An ask buried in somebody’s fourth paragraph comes out as a dated task. A request for a meeting becomes work Point takes on, running the scheduling exchange itself and writing the agreed time into your real calendar. A quiet thread comes back to you before it goes cold, and a standing request can watch for a condition and tell you when it happens.
The other difference is coverage. Copilot’s ranking begins on the day it’s switched on, and looks forward from there. Point weighs what’s in the mailbox now, and a rule that moved something into a folder keeps it in view.
Then there’s the question this whole page keeps circling. Where does an assistant’s opinion get stored, and who else can see it? Copilot’s ranking shows in the Outlook message list, and its summaries and answers live in the Copilot surface you opened them from. Point’s judgment goes onto the mail itself. Three ordinary Outlook categories, Now, Later and Other, are stamped on the real messages. A mailbox sorted at your desk is sorted on your phone and in the browser too, in whatever client you happen to open next. File a thread and it’s archived in the actual Outlook mailbox, in the place you’d go looking for it. Everything you built stays where it is, from the folder tree to the signatures, and precisely what the connection touches is set out in the Microsoft 365 path. What a summary owes its reader, and where one stops, is the summary before you open a thing.
Autonomy is set per kind of action rather than in one global switch, on a scale running from suggest-only through review to fully handled. Review is where each kind starts out, so work gets prepared and then waits for you. Wound up to the top, Point acts on its own, and where you make and change that choice is the autonomy dial. An ordered log records what was done, and undo reaches back across it. The one thing no software anywhere can do is pull a message back off a recipient’s server after delivery. Seats are priced per person, and the private beta publishes no figure. The whole inventory sits on the benefits page.
Now the honest boundaries in the other direction, because they’re real. Your firm may already run on Word, Excel, Teams and SharePoint and want one assistant across all of it. That breadth is Copilot’s actual argument, and it stands on this page as well as anywhere else. Point is a layer on mail and calendar, and a slide deck is somebody else’s job. If the only thing you wanted was a shorter read of one long thread, that’s a button you may already own. Point sits on your own mailbox rather than standing in as a shared inbox, so a firm address several people work is a different question with different answers. For a straight account of what Outlook on its own is genuinely good at, weighed against where it stops, there’s Point versus Outlook alone.
Common questions
What are the limitations of Copilot in Outlook?
The documented ones fall into four groups. It works only in your own primary mailbox hosted in Exchange Online, which leaves out shared, delegate, group and archive mailboxes along with anything on-premises. Protected mail is out of reach: S/MIME and Double Key Encryption mail, signed or encrypted mail, mail with IRM, and some sensitivity-labeled mail. Its inbox ranking starts with the mail that arrives after the feature is switched on. It also skips everything a rule delivered to a folder other than the Inbox, along with meeting mail, out-of-office mail, thin messages, non-delivery receipts and quarantined mail. And most of what people mean by the name needs a paid add-on license on top of a qualifying Microsoft 365 plan.
Does Copilot work with a shared mailbox in Outlook?
No, and Microsoft says so directly. Copilot scenarios in Outlook “are not available on a user’s archive mailbox, group mailboxes, or shared and delegate mailboxes that they have access to”. This is the limit that catches small firms hardest, because the address under the most pressure is usually the one belonging to the business rather than to a person. The entitlement follows each individual’s own primary mailbox, so buying more licenses buys more personal inboxes and leaves the firm address where it is.
Why is the Copilot button missing in my Outlook?
Four things to check, in order of likelihood: the license, the client the mailbox is open in, the mailbox itself, then a live defect. Chat is only offered on a work or school account in new Outlook for Windows or Outlook on the web. Older Outlook for Mac is out. A mailbox that lives outside Exchange Online produces a Copilot icon that’s present but dimmed, and it stays shut. And Microsoft has an open issue, updated August 5, 2026 and still under investigation, in which classic Outlook for Windows loses its Copilot entry points after updating to build 20026.20182 or higher, with new Outlook or Outlook on the web given as the workaround.
Does Copilot in Outlook cost extra?
Partly. Microsoft 365 Copilot Chat is included at no additional cost for Entra account users with an eligible Microsoft 365 subscription, and inside Outlook it answers questions about your inbox and calendar and takes some actions. The features most people mean by Copilot in Outlook sit behind the paid Microsoft 365 Copilot add-on. That one is listed at $30.00 user/month paid yearly with an annual commitment, and it requires a separate qualifying Microsoft 365 license underneath it. Microsoft states there’s no trial of the paid add-on.
Can Copilot read encrypted or protected email?
No. Microsoft states that Copilot in Outlook cannot access S/MIME or Double Key Encryption encrypted emails, and that its features are unsupported on signed or encrypted mail, mail with IRM applied, and some sensitivity-labeled mail. Encrypted messages whose content cannot be seen are excluded from the inbox ranking too. That’s the encryption working rather than the assistant failing. It does mean the most carefully protected correspondence in a practice is the correspondence Copilot contributes least to.
Why is Copilot not prioritizing my old emails?
Because the ranking only ever looks forward. Microsoft states that Copilot prioritizes email received after the feature was turned on, and that it does not prioritize older, existing messages. Separately, changing your criteria applies only to future mail, because Copilot “does not go back and re-evaluate or change the priorities of mail you’ve already received”. A backlog therefore sits outside the feature’s reach permanently, rather than until it catches up, and any tuning you do is a prediction about mail still to arrive.
Does Copilot in Outlook work in classic Outlook?
Some of it. Microsoft’s requirements page says Copilot works with classic and new Outlook, and the summarize and draft features do appear in classic Outlook. Chat is documented as available only in new Outlook for Windows and Outlook on the web, on a work or school account. Classic Outlook is also where the current known issue lives, with Copilot entry points disappearing after a specific build and Microsoft pointing affected users at a different client while it investigates.
Can my administrator see what I asked Copilot?
Yes. Microsoft states that the stored data includes your prompt and Copilot’s response together with citations to whatever was used to answer it, and that administrators can view and manage that data using Content search or Microsoft Purview and apply retention policies to it. You can delete your own Copilot activity history through the My Account portal. Prompts and responses stay out of the training of the underlying models, and Copilot surfaces only data you already had at least view permission over, so it widens what’s easy to find rather than what you’re allowed to see.
The short version
- Copilot in Outlook works in your own primary mailbox, hosted in Exchange Online, and that’s the whole of its reach. Shared, delegate, group and archive mailboxes are excluded by name, and an on-premises mailbox leaves a Copilot icon that’s dimmed and stays shut.
- Most of what people mean by the name is a paid add-on priced per user per month on top of a qualifying Microsoft 365 plan, sold on an annual commitment with no trial. The included Copilot Chat tier is a smaller thing that answers questions about your inbox and calendar.
- The inbox ranking starts with mail that arrives after you switch it on, and changing its criteria applies from that moment forward.
- It also skips anything a rule filed outside the Inbox, along with meeting mail, out-of-office replies, thin messages, non-delivery receipts, quarantined mail and mail the sender marked low importance. A well-organized mailbox shrinks the slice it sees.
- Encrypted, signed, rights-managed and some labeled messages are out of reach entirely, which inverts the usual priority: the mail you protected hardest gets the least help.
- Everything except the priority tag runs when you ask, on a thread you already opened. It shortens the reading, not the deciding.
- Your writing voice is an instruction paragraph you author and maintain, rather than a habit picked up from your sent mail, and it needs a license of its own.
- Prompts and answers are stored, searchable by your administrator and subject to retention policy, and they stay out of the models’ training.
- What all of that leaves is the part of the morning that happens before the first message is open. Point reads for the request inside each message and the date attached to it, puts the mailbox in that order, and writes what it decides onto the real Outlook messages, so one mailbox carries the whole of it.