The academic messaging system of Nantes has changed since January 12, 2026. The old academic webmail (webmel.ac-nantes.fr) has been permanently discontinued, replaced by a national messaging system under Zimbra, accessible at the address messagerie.education.gouv.fr. Properly configuring this new mailbox requires knowledge of the new servers, associated ports, and some settings specific to the 2026 back-to-school context.
Cyberattack of Summer 2026: What Has Changed for Nantes Users
Before discussing configuration, it is essential to understand why so many teachers in the Nantes academy are struggling to access their messaging this school year. A nationwide cyberattack in late July 2026 led to the suspension or significant degradation of access to professional messaging and several business applications.
The Nantes academy is among the academies particularly affected. By late August and early September 2026, many staff still had partial or non-existent access to their mailbox, with very variable behaviors depending on the devices and configurations used. The recovery has been announced as gradual, spread over several weeks.
This context explains why some configuration manipulations fail even when the entered parameters are correct. If a connection error message appears, the cause may be a temporary unavailability on the server side, not a misconfiguration on your part. Before reconfiguring everything, checking the service status on the official channels of the academy remains the first logical step. To delve into each step of the setup, a guide to the Nantes academic mail details the entire procedure.
IMAP and SMTP Servers of the National Zimbra Messaging System
The transition to the national messaging system has changed the addresses of the servers. The old academy-specific servers (imap.ac-nantes.fr, smtp.ac-nantes.fr) are no longer functional. Any configuration that still references them must be updated.
Here are the parameters to use for the national messaging system:
- Incoming IMAP Server: imap.education.gouv.fr, port 993, SSL/TLS encryption. This protocol synchronizes messages between the server and your device, allowing you to access the same emails on your smartphone, tablet, and computer.
- Outgoing SMTP Server: smtp.education.gouv.fr, port 587, STARTTLS encryption. This protocol manages the sending of your messages. STARTTLS negotiates encryption after the initial connection, distinguishing it from SSL/TLS where encryption starts immediately.
- Username: your usual academic identifier (format firstname.lastname in most cases). The password remains that of your academic account.
The announced quota for this national messaging system is 20 GB, a capacity well above what the old academic webmail offered.
Configuration on Android Smartphones and iOS Devices
On an Android device, the procedure goes through the system settings. Open Settings, then Accounts (or Accounts and Sync depending on the version), select Add Account, choose Email, then IMAP.
The fields to fill in follow the parameters listed above. One point deserves attention: the “Security Type” field of the incoming server must be set to SSL/TLS, while that of the outgoing server must indicate STARTTLS. Confusing these two settings is the most common source of error.
Managing Security Certificates
During the first connection, your device may display a warning regarding the security certificates of the server. This behavior is normal with the servers of the National Education, whose certificates are not always natively recognized by all operating systems.
Accepting the certificate allows you to continue the configuration. On iOS, this validation is done through a specific screen where you must explicitly authorize the connection. On Android, some versions require checking “Accept all certificates” in the advanced settings of the email account.
Resolving Persistent Connection Issues After Configuration
A technically correct configuration does not guarantee immediate access in the current context. Several situations can block the connection even with the correct parameters.
- The academic password has been reset following the cyberattack. Some staff received a new temporary password without being clearly informed. Attempting a reset via the ARENA portal or contacting your institution’s IT service can clarify this doubt.
- The email application used caches the old settings. Deleting the academic email account from the device and then recreating it entirely (rather than modifying the existing settings) avoids configuration conflicts.
- Network restrictions at some institutions block port 587 or port 993. Testing the connection from a home network or via mobile data can help isolate this type of problem.
If access remains impossible after these checks, the problem likely relates to the gradual resumption of services after the cyberattack. In this case, waiting a few days before trying again remains the only realistic option.
Difference Between Zimbra Web and Native Mail Client
Accessing messagerie.education.gouv.fr from a web browser provides access to the full Zimbra interface, with calendar, contacts, and folder management. This interface operates independently of any IMAP or SMTP configuration on your device.
Configuring a native mail client (such as the one on your smartphone or software like Thunderbird) offers real-time notification reception and offline access to already synchronized messages. The two access modes are complementary, not exclusive.
The national messaging system under Zimbra represents a sustainable infrastructure change for all academies. The server parameters described here will remain valid as long as this system is in place. For staff of the Nantes academy, the priority remains to ensure that the old ac-nantes.fr servers have indeed been replaced on all devices configured before January 2026.
