Table of Contents
Why Is Microsoft Teams So Slow on Windows and Can the 2026 Update Fix It?
If you rely on Microsoft Teams for your daily work, you likely already know it can burden your system. Many users report that the application feels heavy, takes a long time to launch, and consumes significant memory even when idle. This sluggishness occurs because Teams operates as a large web application wrapped in a container rather than a purely native program. It must constantly maintain connections to chats, calendars, files, and various Microsoft services, which drains system resources.
The Upcoming Architecture Change
Microsoft has acknowledged these performance bottlenecks and is preparing a significant architectural shift scheduled for January 2026. The company will split the Teams client into two distinct processes to better manage system resources:
- ms-teams.exe: This remains the primary process. It will continue to power your user interface, chats, file sharing, and general navigation.
- ms-teams_modulehost.exe: This is a new child process dedicated strictly to “calling” capabilities. It will handle audio, video, and screen sharing independently from the rest of the app.
Why This Split Improves Stability
This separation is a strategic move to isolate potential failures. Currently, if a bug occurs during a call, it can destabilize the entire application. By moving calling features to ms-teams_modulehost.exe, Microsoft ensures that a glitch in a meeting is less likely to crash your chat or navigation windows. This division should also improve the application’s startup time, as the main interface no longer needs to load the entire calling stack immediately upon launch.
The WebView2 Limitation
While this update offers practical improvements, it does not solve the root cause of the high RAM usage: WebView2. Microsoft Teams moved from Electron to WebView2 (Edge’s rendering engine) to improve efficiency, but it remains a web-based framework.
Unlike “native” applications written specifically for Windows hardware (using languages like C++ or C# with WinUI), WebView2 apps essentially run a web browser in the background. This approach allows Microsoft to update features quickly across different platforms, but it inherently requires more memory and processing power than native code. Until Microsoft rewrites Teams as a fully native application, memory consumption will likely remain higher than users prefer.
Critical Action for IT Administrators
For enterprise environments, this update requires a small but crucial preparation. Because ms-teams_modulehost.exe is a completely new executable file, strict security software might not recognize it immediately.
Recommendation: You must update your antivirus or endpoint protection allowlists to include ms-teams_modulehost.exe before January 2026. If you fail to do this, your security software might block the process, causing calls to drop or fail to start entirely. The rollout will begin in January and is expected to complete by February 2026.