Microsoft is continuing to bring Copilot features into the classic Outlook for Windows experience, and the latest addition is more practical than many broad “AI in email” announcements. According to Windows Latest, Outlook Classic is getting an “Explain This” action that lets a user highlight text inside an email and ask Copilot for a contextual explanation. Instead of summarizing an entire thread or writing a reply, this feature is aimed at quick understanding: unfamiliar acronyms, internal jargon, policy language, technical terms, or dense instructions can be explained in the context of the message the user is already reading.

For IT departments and power users, the important point is not simply that Microsoft is adding more AI to Outlook. It is that this feature behaves like a just-in-time clarification tool rather than another inbox-wide automation. That makes it easier to evaluate, train for, and govern than features that automatically summarize or rewrite content in the background.

What “Explain This” does in Outlook Classic

The feature is designed around text selection. A user opens an email, highlights a word, phrase, or sentence, and then triggers Copilot to explain the selection while considering the surrounding email content. In a support or operations scenario, that could mean selecting a term such as “BSOD,” “conditional access,” “retention hold,” “RPO,” or a vendor-specific product name and receiving an explanation that fits the message instead of a generic dictionary definition.

That contextual behavior matters. A plain web search can define an acronym, but it may not tell the user why that acronym appears in a specific outage notice, compliance message, procurement thread, or change-management email. If Copilot can correctly use the email as context, the feature may reduce follow-up questions and help non-specialists understand technical messages faster.

Windows Latest reports that Microsoft expects the rollout to complete by the end of September, with many users seeing it earlier in the month. The feature requires a Microsoft 365 Copilot subscription, so organizations that have not licensed Copilot should not expect it to appear as a standard Outlook capability.

Why this is useful for IT users

Email remains where many business decisions, security alerts, and operational instructions actually land. Even in organizations that rely heavily on Teams or ticketing systems, Outlook is still a common destination for vendor advisories, executive approvals, incident updates, audit requests, and HR or finance policies.

“Explain This” could be helpful in several everyday cases:

- A help desk analyst receives a vendor bulletin and needs a quick explanation of a technical phrase before escalating.
- A manager reads an IT change notification and wants to understand the impact without interrupting the infrastructure team.
- A finance or legal user receives a security-related request and needs plain-language clarification before taking action.
- A multilingual or cross-functional team member encounters internal shorthand that is obvious to one department but not another.

The most promising aspect is that the user chooses when to invoke the tool. That is different from features that automatically insert AI into every message workflow. For many organizations, opt-in interaction is easier to introduce because users can be trained to treat Copilot output as assistance, not as an authoritative system of record.

Admin and compliance considerations

Before encouraging use, Microsoft 365 administrators should confirm who is licensed for Copilot, what data protection rules apply in their tenant, and whether Outlook Copilot settings match organizational policy. Windows Latest notes that Outlook Classic now includes Copilot Settings under File, including a way to control Copilot behavior in Outlook. Admins should test these settings on managed devices and document what end users can change themselves.

Practical rollout steps include:

- Verify that only intended user groups have Microsoft 365 Copilot licenses.
- Review Microsoft Purview, sensitivity label, and data-loss-prevention policies that affect email content.
- Update internal AI usage guidance to cover selected-text explanations in Outlook.
- Remind users not to treat AI explanations as approval to bypass security, legal, or compliance processes.
- Test the feature with realistic internal messages before promoting it broadly.

The key governance question is whether users understand the boundary between “this helps me understand a message” and “this makes a decision for me.” A Copilot explanation can be useful, but it should not replace official policy, administrator guidance, or expert review in regulated workflows.

Training users to get better results

If your organization enables the feature, short training will go a long way. Users should highlight a specific phrase rather than an entire email when they need a targeted explanation. They should also compare the answer against the message context and ask a human expert when the topic involves security actions, payments, legal obligations, or customer-impacting decisions.

It is also worth teaching users that context can cut both ways. Copilot may provide a more relevant answer when it reads surrounding text, but the quality of the explanation still depends on the content of the email and the model’s interpretation. The safest framing is: use “Explain This” to accelerate comprehension, then verify before acting.

Bottom line

Outlook Classic users often handle complex information in a familiar but aging desktop client. Bringing targeted Copilot assistance into that environment makes sense, especially when it is user-triggered and focused on selected text. For Microsoft 365 admins, this is a good moment to review Copilot licensing, Outlook settings, and end-user AI guidance before the feature becomes widely visible.

If implemented carefully, “Explain This” could be one of the more genuinely useful Copilot additions to Outlook Classic: not a replacement for expertise, but a convenient way to turn confusing email language into something users can understand quickly.

Source: Windows Latest source