French CNRS Ditches Microsoft Exchange for Open-Source Collaborative Messaging

The French National Centre for Scientific Research (CNRS) is abandoning Microsoft Exchange in favor of a collaborative messaging platform built on open-source software. This transition to PARTAGE, a platform operated by the RENATER network, is expected to save the organization €3.5 million annually while strengthening its control over digital infrastructure and data.

Strategic Shift Away from GAFAM

Officially announced on November 3, 2026, this decision aligns with the CNRS’s broader strategy to reduce its dependence on GAFAM (Google, Apple, Facebook, Amazon, and Microsoft) services, with a specific focus on minimizing reliance on Microsoft solutions.

The migration impacts approximately 35,000 staff members and nearly 50,000 email boxes, including individual accounts, shared mailboxes, and service-specific accounts.

Technical Details: From Exchange to Zimbra

Technically, Microsoft Exchange is being replaced by Zimbra, an open-source solution with accessible and modifiable source code. Zimbra is integrated into PARTAGE, RENATER’s collaborative messaging service, which is offered in a SaaS (Software as a Service) model.

This arrangement entrusts operations to a specialized public operator focused on digital infrastructure for higher education and research.

Digital Sovereignty and Data Control

Beyond the technical upgrade, this choice addresses critical issues of digital sovereignty. RENATER’s infrastructure—including its data centers and communication networks—ensures that data remains hosted within French territory.

For an organization like the CNRS, where electronic communications may contain sensitive scientific information, maintaining control over data hosting is a strategic imperative.