Microsoft has announced a major architectural upgrade to Microsoft Teams for Windows (desktop client), which will be implemented in January 2026 and aims to improve performance in calls and meetings . The company is moving forward with the creation of a new process that will exclusively manage calling functions, aiming for faster startup and smoother operation for millions of enterprise users.
New process for calls: ms-teams_modulehost.exe changes architecture
According to Microsoft , the upcoming process named ms-teams_modulehost.exe will take over the application's call stack, offloading the main ms-teams.exe process . The company says this new approach allows for better utilization of system resources and reduces application startup times — one of the most common complaints from companies and users.
See also: Screen Recording Prevention: New Teams security feature
After the change is released, Teams will handle calling functionality “behind the scenes,” with no changes or training required from end users. The experience will remain familiar, but faster and more consistent.
What IT admins need to know
Although users will not need to do anything, IT administrators are urged to prepare in advance.
Microsoft recommends that organizations:
- add the new process ms-teams_modulehost.exe to the lists of allowed files of security systems,
- update endpoints to avoid false positives from antivirus or EDR tools,
- Prepare the help desk to avoid confusion when an unknown executable appears in user reports.
The company emphasizes that the lack of proper adjustment of security systems can lead to blocked calls or errors when starting Teams.
Release schedule
The release begins in early January 2026, covering:
- global environments,
- the GCC,
- GCC High,
- as well as the tenants of the US Department of Defense.
The transition is expected to be completed by the end of January 2026.
See also: Microsoft Teams: New “Chat with Anyone” feature exposes users to Phishing attacks
New security features in Teams in 2025
The change to the call handler isn't the only upgrade step. Since the beginning of the year, Microsoft has accelerated investments in content protection within Teams.
Among the latest features:
- Warnings when users send or receive links that have been marked as malicious.
- Enhanced analysis of URLs and suspicious files within chats and channels.
- Automatically block attempts to take screenshots during meetings — a feature aimed at protecting the privacy of corporate discussions.
- Ability to report messages that have been incorrectly marked as dangerous, improving false-positive detection mechanisms.
With these features, Teams is solidifying itself as one of the most actively supported communication platforms when it comes to security at the enterprise level.
Microsoft Teams: Why this change matters
The architectural transition to a separate process for calls is not a simple internal modification. It represents a more modern design logic, similar to that followed by browsers and high-end applications:
- Greater stability: If one function “crashes”, the entire application is not affected.
- Faster startup: The application does not load the call engine from the first moment.
- Optimal CPU/GPU management: Important for high-quality meetings, screen sharing, and real-time audio/video processing.
For enterprise environments with hundreds or thousands of users, such changes translate into fewer downtime tickets and higher productivity.
See also: Warning! Serious vulnerabilities in Microsoft Teams
Parallel upgrades to the Windows ecosystem
Alongside the changes to Teams, Microsoft has also begun testing File Explorer preloading in Windows 11, aiming to significantly reduce File Explorer opening times. The move is part of the company's broader strategy to boost the performance of core tools in its operating system.
Source: www.bleepingcomputer.com
