Table of Contents
Summary
- Introduction of a new process, ms-teams_modulehost.exe, for improved performance of calling features in Teams Desktop Client for Windows.
- The new process will run alongside the main application process, ms-teams.exe, focusing on optimizing resource usage.
- No changes to user workflows or the user interface; admins need to ensure security software permits the new process.
- Preparation needed includes allowlisting the new process and updating helpdesk staff and internal documentation.
- The change is categorized as a feature update with significant impacts for both users and administrators.
Admin Impact: Medium
User Impact: Low
Release Start: 01 Jan 2026
Release End: 31 Jan 2026
Services: Teams
Category: Plan for change
Tags: Feature Update, User Adoption, Admin Action
History
11/25/2025 Item Added to Message Center
Microsoft Message
Updated November 26, 2025: We have updated the content below to provide additional information. Thank you for your feedback.
Introduction
We’re improving the performance and startup time of calling features in the Microsoft Teams Desktop Client for Windows. To achieve this, we’re introducing a new child process named ms-teams_modulehost.exe that will handle the calling stack separately from the main application process (ms-teams.exe). This change optimizes resource usage and enhances meeting experiences.
When this will happen
Worldwide, GCC, GCC High, and DoD: Rollout will begin early January 2026 and complete by late January 2026.
Note: Timelines may shift due to year-end feature flag rollout freeze.
How this affects your organization
Who is affected: All users running the Teams Desktop Client on Windows.
What will happen:
- A new process (ms-teams_modulehost.exe) will appear in Task Manager under the main Teams process (ms-teams.exe).
- This process is dedicated to calling features and improves performance.
- No changes to user workflows or UI; however, admins should ensure endpoint and security software allow this new process.
What you can do to prepare
- Update endpoint management and security software to allowlist ms-teams_modulehost.exe alongside ms-teams.exe.
- Communicate this change to helpdesk staff to avoid confusion during troubleshooting.
- Update internal documentation if you reference Teams process names.
- Make sure the same QoS settings applied to ms-teams.exe are also applied to ms-teams_modulehost.exe. Refer to this page for details: Implement Quality of Service (QoS) in Microsoft Teams
- DO NOT remove QoS settings of ms-teams.exe. Only add QoS settings for ms-teams_modulehost.exe.
Compliance considerations
No compliance considerations identified, review as appropriate for your organization.