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(Updated) Executable name update for Microsoft 365 Copilot app for Windows
MC1141945 · build prod-20251231-200323
Category
planForChange
Severity
normal
Major change
False
Last modified
2025-09-30 19:12:33
Summary source
Azure OpenAI (gpt-4.1)
Action by (Graph)
Action by (AI)
Services
Microsoft 365 suite, Microsoft 365 apps, Microsoft Copilot (Microsoft 365)
Tags
Updated message, Feature update, User impact, Admin impact
Master tags
Roadmap IDs

One-line summary

The Microsoft 365 Copilot app executable on Windows will change from Webviewhost.exe to M365Copilot.exe with the next app update after late October 2025.

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Details

Summary
The Microsoft 365 Copilot app for Windows will change its executable name from Webviewhost.exe to M365Copilot.exe after late October 2025. The update is automatic for Microsoft Store users with auto-updates enabled. No functionality changes occur; update dependencies if needed.

Body (from Message Center)

Updated September 30, 2025: We have updated the timeline. Thank you for your patience. 

To better reflect the identity and functionality of the Microsoft 365 Copilot app, we are updating the executable name on Windows devices. This change improves clarity for IT admins, developers, and users managing diagnostics or process monitoring.

When this will happen:

This update will roll out to affected users with the next app update after late October 2025 (previously late September).

How this affects your organization:

With the change, the executable name for the Microsoft 365 Copilot Windows app will change from Webviewhost.exe to M365Copilot.exe. For users who installed the app via the Microsoft Store, the update will happen automatically on September 20 if their device settings allow for automatic updates. For users who installed the app through other platforms or have settings that do not allow automatic updates, the change will happen once users update their app.

This update does not affect app functionality or user experience.

What you can do to prepare:

No action is required unless your organization has dependencies on Webviewhost.exe. If so, update those references to M365Copilot.exe to ensure continued functionality.

Compliance considerations:

No compliance considerations identified, review as appropriate for your organization.

Raw JSON (for debugging)

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{
  "snapshot_item": {
    "action_required_by": null,
    "ai_action_required_by": null,
    "ai_actions": [
      "Update dependencies referencing Webviewhost.exe to M365Copilot.exe if applicable"
    ],
    "ai_master_tags": [],
    "ai_model": "gpt-4.1",
    "ai_summary": "The Microsoft 365 Copilot app executable on Windows will change from Webviewhost.exe to M365Copilot.exe with the next app update after late October 2025.",
    "ai_topics": [
      "Microsoft 365",
      "Microsoft 365 Apps",
      "Copilot"
    ],
    "category": "planForChange",
    "details_map": {
      "Summary": "The Microsoft 365 Copilot app for Windows will change its executable name from Webviewhost.exe to M365Copilot.exe after late October 2025. The update is automatic for Microsoft Store users with auto-updates enabled. No functionality changes occur; update dependencies if needed."
    },
    "id": "MC1141945",
    "importance": 1,
    "is_major_change": false,
    "last_modified": "2025-09-30T19:12:33Z",
    "ms_products": [
      "Microsoft 365",
      "Microsoft 365 Apps",
      "Copilot"
    ],
    "platforms": null,
    "roadmap_ids": [],
    "services": [
      "Microsoft 365 suite",
      "Microsoft 365 apps",
      "Microsoft Copilot (Microsoft 365)"
    ],
    "severity": "normal",
    "tags": [
      "Updated message",
      "Feature update",
      "User impact",
      "Admin impact"
    ],
    "title": "(Updated) Executable name update for Microsoft 365 Copilot app for Windows"
  }
}