Table of Contents
Summarize Attachment Feature is an Example of New Features Needed to Maintain Customer Interest
Introducing a new technology is hard. The great expectations created at the initial launch soon meets the hard reality of deployment and things don’t get better until the technology has had time to bake. This is as true for Microsoft 365 Copilot as for any other major technology. I see people questioning whether the $30/user/month really delivers any benefits, with real concern over whether people use any of the purported time saved through Copilot interventions doing anything more valuable than drinking more coffee.
News that the U.S. Better Business Bureau forced Microsoft to change some of the claims it makes about how Microsoft 365 Copilot affects user productivity doesn’t help the case for AI-based assistance. And lukewarm or mildly enthusiastic (but independent) reports about Copilot usage in organizations, like the recent UK Government report based on a 3-month trial for 20,000 employees don’t bolster the case much either.
All Microsoft can do is continue to push out updates and new AI-based features to keep customer interest while Copilot matures to become more useful in day-to-day activities. The result is a flood of new Copilot-related features, not all of which seem valuable except in specific cases. I don’t know whether AI-informed People Skills will become popular (some HR professionals that I know like People Skills a lot). Those in the Power Platform world (now with 56 million monthly active users according to data made available at Microsoft’s FY25 Q3 results) see lots of changes to make Copilot agents more productive. I do like the ability to upload documents to agents for the agents to reason over.
Summarizing Attachments
All of which brings me to the update described in message center notification MC1073094 (13 May 2025, Microsoft 365 Roadmap item 475249). It’s an example of a recent Copilot enhancement to help users process “classic” email attachments faster. Even though cloudy attachments are preferable in many respects, many people still send files instead of links.
Copilot has been able to summarize cloudy attachments for email for quite a while. Now, when a message with one or more classic file attachments arrives, users with a Microsoft 365 license see a new summarize option for Office and PDF attachments. The feature is available in the New Outlook for Windows, OWA, Outlook mobile, and Outlook for Mac, but not for Outlook classic. Microsoft is rolling out the update now with estimated completion by late August 2025.
Figure 1 shows the general idea. A Word file is attached to a message. Clicking the summarize option from the drop-down menu beside the attachment causes Copilot to create and display the summary for the file inside the Summary by Copilot panel (or card). If a message has multiple file attachments, the summarize option must be invoked separately.
Copilot cannot process encrypted attachments (using sensitivity labels or another encryption mechanism).
No Archived Messages
My archive mailbox is full of attachments from long-forgotten projects, including files related to some legal cases that I was involved with. I was curious to see what sense Copilot might extract from some of the PDFs and Word documents from those cases. Oddly, Outlook won’t summarize any of the attachments for messages stored in an archive mailbox. To generate a summary for these files, you must open download and open Office files in a desktop or web app and use the Copilot options available in the app.
Thinking about why this might be so, I guess the logic is that attachments for archived messages probably aren’t of very high interest, and if someone goes to the trouble of finding an archived message, they have a purpose for doing so and won’t mind opening attachments to view content. On the other hand, I could be overthinking things and Microsoft simply designed the feature to work only with messages from the primary mailbox.
The Value of Small Changes
Over my many years of work, I cannot say how many emails I have received with file attachments. Being able to see a quick summary of an attachment is a good example of how AI can be effective. The feature works well because the AI has just one file to process, so it’s unlikely that hallucinations or other issues will occur. You might disagree with points made in the summary, but having the summary is a timesaver and a great starting point for understanding whether a file contains anything important.
Another example of a small but interesting change is the ability to create a meeting from an Outlook email thread (MC1090693, 9 June 2025, Microsoft 365 roadmap item 494154). The idea is that Copilot scans an email thread to determine the topic for a meeting and its participants and creates a meeting invitation ready to go. This kind of thing doesn’t need AI because existing Graph APIs can do the work, but Copilot integrates the work into a new Schedule with Copilot option (only for email threads with sufficient data to base a meeting upon). According the roadmap item, this feature is for the mobile clients, but I bet it will be available in the new Outlook and OWA too.
In the overall scheme of Copilot, delivering Outlook features to make small tasks easier is not important. However, changes that reduce friction for users are important and collectively a bunch of changes like this might just be enough to convince an organization that they really can’t live without Copilot.
Insight like this doesn’t come easily. You’ve got to know the technology and understand how to look behind the scenes. Benefit from the knowledge and experience of the Office 365 for IT Pros team by subscribing to the best eBook covering Office 365 and the wider Microsoft 365 ecosystem.