diff --git a/mail_environment/README.rst b/mail_environment/README.rst
index d0f79cea0..fb7ee8f5a 100644
--- a/mail_environment/README.rst
+++ b/mail_environment/README.rst
@@ -1,7 +1,3 @@
-.. image:: https://odoo-community.org/readme-banner-image
-   :target: https://odoo-community.org/get-involved?utm_source=readme
-   :alt: Odoo Community Association
-
 ==========================================
 Mail configuration with server_environment
 ==========================================
@@ -17,7 +13,7 @@ Mail configuration with server_environment
 .. |badge1| image:: https://img.shields.io/badge/maturity-Beta-yellow.png
     :target: https://odoo-community.org/page/development-status
     :alt: Beta
-.. |badge2| image:: https://img.shields.io/badge/license-AGPL--3-blue.png
+.. |badge2| image:: https://img.shields.io/badge/licence-AGPL--3-blue.png
     :target: http://www.gnu.org/licenses/agpl-3.0-standalone.html
     :alt: License: AGPL-3
 .. |badge3| image:: https://img.shields.io/badge/github-OCA%2Fserver--env-lightgray.png?logo=github
@@ -103,8 +99,8 @@ file.
 Known issues / Roadmap
 ======================
 
-- Due to the special nature of this addon, you cannot test it on the OCA
-  runbot.
+-  Due to the special nature of this addon, you cannot test it on the
+   OCA runbot.
 
 Bug Tracker
 ===========
@@ -127,12 +123,12 @@ Authors
 Contributors
 ------------
 
-- Nicolas Bessi <nicolas.bessi@camptocamp.com>
-- Yannick Vaucher <yannick.vaucher@camptocamp.com>
-- Guewen Baconnier <guewen.baconnier@camptocamp.com>
-- Joël Grand-Guillaume <joel.grandguillaume@camptocamp.com>
-- Holger Brunn <hbrunn@therp.nl>
-- Alexandre Fayolle <alexandre.fayolle@camptocamp.com>
+-  Nicolas Bessi <nicolas.bessi@camptocamp.com>
+-  Yannick Vaucher <yannick.vaucher@camptocamp.com>
+-  Guewen Baconnier <guewen.baconnier@camptocamp.com>
+-  Joël Grand-Guillaume <joel.grandguillaume@camptocamp.com>
+-  Holger Brunn <hbrunn@therp.nl>
+-  Alexandre Fayolle <alexandre.fayolle@camptocamp.com>
 
 Maintainers
 -----------
diff --git a/mail_environment/__init__.py b/mail_environment/__init__.py
index 0650744f6..071962a35 100644
--- a/mail_environment/__init__.py
+++ b/mail_environment/__init__.py
@@ -1 +1,2 @@
 from . import models
+from .hooks import uninstall_hook
diff --git a/mail_environment/__manifest__.py b/mail_environment/__manifest__.py
index b20d02d35..a579b0fa1 100644
--- a/mail_environment/__manifest__.py
+++ b/mail_environment/__manifest__.py
@@ -10,4 +10,5 @@
     "license": "AGPL-3",
     "website": "https://github.com/OCA/server-env",
     "depends": ["mail", "server_environment"],
+    "uninstall_hook": "uninstall_hook",
 }
diff --git a/mail_environment/hooks.py b/mail_environment/hooks.py
new file mode 100644
index 000000000..bdab5d78c
--- /dev/null
+++ b/mail_environment/hooks.py
@@ -0,0 +1,43 @@
+# Copyright 2026 Camptocamp (https://www.camptocamp.com)
+from odoo.addons.server_environment.uninstall import restore_env_managed_columns
+
+
+def uninstall_hook(env):
+    """Restore database columns that server.env.mixin dropped for mail models.
+
+    When mail_environment is uninstalled, ``ir.mail_server`` and
+    ``fetchmail.server`` would be left without the columns that the ORM
+    dropped when this addon was first installed. This hook recreates those
+    columns and repopulates them with the current effective values so the
+    database remains usable after removal.
+
+    After uninstalling this module, an Odoo server restart is required.
+    Field definitions referencing the compute methods of the mixin persist in memory
+    until the Python process restarts.
+    """
+    restore_env_managed_columns(
+        env,
+        "ir.mail_server",
+        [
+            "smtp_host",
+            "smtp_port",
+            "smtp_user",
+            "smtp_pass",
+            "smtp_encryption",
+            "smtp_authentication",
+        ],
+    )
+    restore_env_managed_columns(
+        env,
+        "fetchmail.server",
+        [
+            "server",
+            "port",
+            "server_type",
+            "user",
+            "password",
+            "is_ssl",
+            "attach",
+            "original",
+        ],
+    )
diff --git a/mail_environment/static/description/index.html b/mail_environment/static/description/index.html
index 0f434f77e..135388a1d 100644
--- a/mail_environment/static/description/index.html
+++ b/mail_environment/static/description/index.html
@@ -3,7 +3,7 @@
 <head>
 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
 <meta name="generator" content="Docutils: https://docutils.sourceforge.io/" />
-<title>README.rst</title>
+<title>Mail configuration with server_environment</title>
 <style type="text/css">
 
 /*
@@ -360,14 +360,9 @@
 </style>
 </head>
 <body>
-<div class="document">
+<div class="document" id="mail-configuration-with-server-environment">
+<h1 class="title">Mail configuration with server_environment</h1>
 
-
-<a class="reference external image-reference" href="https://odoo-community.org/get-involved?utm_source=readme">
-<img alt="Odoo Community Association" src="https://odoo-community.org/readme-banner-image" />
-</a>
-<div class="section" id="mail-configuration-with-server-environment">
-<h1>Mail configuration with server_environment</h1>
 <!-- !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 !! This file is generated by oca-gen-addon-readme !!
 !! changes will be overwritten.                   !!
@@ -395,12 +390,12 @@ <h1>Mail configuration with server_environment</h1>
 </ul>
 </div>
 <div class="section" id="installation">
-<h2><a class="toc-backref" href="#toc-entry-1">Installation</a></h2>
+<h1><a class="toc-backref" href="#toc-entry-1">Installation</a></h1>
 <p>To install this module, you need to have the server_environment module
 installed and properly configured.</p>
 </div>
 <div class="section" id="configuration">
-<h2><a class="toc-backref" href="#toc-entry-2">Configuration</a></h2>
+<h1><a class="toc-backref" href="#toc-entry-2">Configuration</a></h1>
 <p>With this module installed, the incoming and outgoing mail servers are
 configured in the server_environment_files module (which is a module you
 should provide, see the documentation of server_environment for more
@@ -440,20 +435,20 @@ <h2><a class="toc-backref" href="#toc-entry-2">Configuration</a></h2>
 mail server with the field name set to “odoo_pop_mail1”.</p>
 </div>
 <div class="section" id="usage">
-<h2><a class="toc-backref" href="#toc-entry-3">Usage</a></h2>
+<h1><a class="toc-backref" href="#toc-entry-3">Usage</a></h1>
 <p>Once configured, Odoo will read the mail servers values from the
 configuration file related to each environment defined in the main Odoo
 file.</p>
 </div>
 <div class="section" id="known-issues-roadmap">
-<h2><a class="toc-backref" href="#toc-entry-4">Known issues / Roadmap</a></h2>
+<h1><a class="toc-backref" href="#toc-entry-4">Known issues / Roadmap</a></h1>
 <ul class="simple">
-<li>Due to the special nature of this addon, you cannot test it on the OCA
-runbot.</li>
+<li>Due to the special nature of this addon, you cannot test it on the
+OCA runbot.</li>
 </ul>
 </div>
 <div class="section" id="bug-tracker">
-<h2><a class="toc-backref" href="#toc-entry-5">Bug Tracker</a></h2>
+<h1><a class="toc-backref" href="#toc-entry-5">Bug Tracker</a></h1>
 <p>Bugs are tracked on <a class="reference external" href="https://github.com/OCA/server-env/issues">GitHub Issues</a>.
 In case of trouble, please check there if your issue has already been reported.
 If you spotted it first, help us to smash it by providing a detailed and welcomed
@@ -461,15 +456,15 @@ <h2><a class="toc-backref" href="#toc-entry-5">Bug Tracker</a></h2>
 <p>Do not contact contributors directly about support or help with technical issues.</p>
 </div>
 <div class="section" id="credits">
-<h2><a class="toc-backref" href="#toc-entry-6">Credits</a></h2>
+<h1><a class="toc-backref" href="#toc-entry-6">Credits</a></h1>
 <div class="section" id="authors">
-<h3><a class="toc-backref" href="#toc-entry-7">Authors</a></h3>
+<h2><a class="toc-backref" href="#toc-entry-7">Authors</a></h2>
 <ul class="simple">
 <li>Camptocamp</li>
 </ul>
 </div>
 <div class="section" id="contributors">
-<h3><a class="toc-backref" href="#toc-entry-8">Contributors</a></h3>
+<h2><a class="toc-backref" href="#toc-entry-8">Contributors</a></h2>
 <ul class="simple">
 <li>Nicolas Bessi &lt;<a class="reference external" href="mailto:nicolas.bessi&#64;camptocamp.com">nicolas.bessi&#64;camptocamp.com</a>&gt;</li>
 <li>Yannick Vaucher &lt;<a class="reference external" href="mailto:yannick.vaucher&#64;camptocamp.com">yannick.vaucher&#64;camptocamp.com</a>&gt;</li>
@@ -480,7 +475,7 @@ <h3><a class="toc-backref" href="#toc-entry-8">Contributors</a></h3>
 </ul>
 </div>
 <div class="section" id="maintainers">
-<h3><a class="toc-backref" href="#toc-entry-9">Maintainers</a></h3>
+<h2><a class="toc-backref" href="#toc-entry-9">Maintainers</a></h2>
 <p>This module is maintained by the OCA.</p>
 <a class="reference external image-reference" href="https://odoo-community.org">
 <img alt="Odoo Community Association" src="https://odoo-community.org/logo.png" />
@@ -493,6 +488,5 @@ <h3><a class="toc-backref" href="#toc-entry-9">Maintainers</a></h3>
 </div>
 </div>
 </div>
-</div>
 </body>
 </html>
diff --git a/mail_environment/tests/test_mail_environment.py b/mail_environment/tests/test_mail_environment.py
index 44c396b2c..c606fc9a9 100644
--- a/mail_environment/tests/test_mail_environment.py
+++ b/mail_environment/tests/test_mail_environment.py
@@ -2,7 +2,10 @@
 # License LGPL-3.0 or later (https://www.gnu.org/licenses/lgpl.html)
 
 
+from odoo.tools import sql
+
 from odoo.addons.server_environment.tests.common import ServerEnvironmentCase
+from odoo.addons.server_environment.uninstall import restore_env_managed_columns
 
 fetchmail_config = """
 [incoming_mail.fetchmail1]
@@ -75,3 +78,221 @@ def test_fetchmail_search_is_ssl(self):
                 fetchmail2,
                 self.env["fetchmail.server"].search([("is_ssl", "!=", True)]),
             )
+
+
+_outgoing_config = """
+[outgoing_mail.test_outgoing]
+smtp_host = smtp.example.com
+smtp_port = 587
+smtp_encryption = starttls
+smtp_authentication = login
+smtp_user = testuser
+smtp_pass = testpass
+"""
+
+_incoming_config = """
+[incoming_mail.test_incoming]
+server = imap.example.com
+port = 993
+server_type = imap
+is_ssl = 1
+user = imap_user
+password = imap_pass
+attach = 1
+original = 0
+"""
+
+
+class TestRestoreEnvManagedColumns(ServerEnvironmentCase):
+    """Test column restoration performed by the uninstall hook."""
+
+    def _drop_columns(self, model_name, field_names):
+        """Drop columns created by restore_env_managed_columns (test cleanup)."""
+        model = self.env[model_name]
+        cr = self.env.cr
+        for field_name in field_names:
+            if sql.column_exists(cr, model._table, field_name):
+                cr.execute(  # noqa: S608
+                    f'ALTER TABLE {model._table} DROP COLUMN "{field_name}"'
+                )
+
+    def test_restore_ir_mail_server_columns(self):
+        """Outgoing mail columns are recreated and populated with config values."""
+        field_names = [
+            "smtp_host",
+            "smtp_port",
+            "smtp_encryption",
+            "smtp_authentication",
+            "smtp_user",
+            "smtp_pass",
+        ]
+        server = self.env["ir.mail_server"].create({"name": "test_outgoing"})
+        try:
+            with self.load_config(public=_outgoing_config):
+                restore_env_managed_columns(self.env, "ir.mail_server", field_names)
+                table = self.env["ir.mail_server"]._table
+                for field_name in field_names:
+                    self.assertTrue(
+                        sql.column_exists(self.env.cr, table, field_name),
+                        f"Column {field_name} was not created",
+                    )
+                self.env.cr.execute(
+                    "SELECT smtp_host, smtp_port, smtp_encryption,"
+                    " smtp_authentication, smtp_user, smtp_pass"
+                    " FROM ir_mail_server WHERE id = %s",
+                    [server.id],
+                )
+                row = self.env.cr.dictfetchone()
+                self.assertEqual(row["smtp_host"], "smtp.example.com")
+                self.assertEqual(row["smtp_port"], 587)
+                self.assertEqual(row["smtp_encryption"], "starttls")
+                self.assertEqual(row["smtp_authentication"], "login")
+                self.assertEqual(row["smtp_user"], "testuser")
+                self.assertEqual(row["smtp_pass"], "testpass")
+        finally:
+            self._drop_columns("ir.mail_server", field_names)
+
+    def test_restore_ir_mail_server_columns_with_default(self):
+        """Columns are populated with default values when no config is loaded."""
+        field_names = ["smtp_host", "smtp_port"]
+        # Write via the inverse to set the x_smtp_host_env_default sparse field.
+        server = self.env["ir.mail_server"].create(
+            {"name": "test_default_outgoing", "smtp_host": "default.example.com"}
+        )
+        try:
+            # No config loaded — values come from x_smtp_host_env_default.
+            restore_env_managed_columns(self.env, "ir.mail_server", field_names)
+            table = self.env["ir.mail_server"]._table
+            self.assertTrue(sql.column_exists(self.env.cr, table, "smtp_host"))
+            self.env.cr.execute(
+                "SELECT smtp_host FROM ir_mail_server WHERE id = %s",
+                [server.id],
+            )
+            self.assertEqual(self.env.cr.fetchone()[0], "default.example.com")
+        finally:
+            self._drop_columns("ir.mail_server", field_names)
+
+    def test_restore_fetchmail_server_columns(self):
+        """Incoming mail columns are recreated and populated with config values."""
+        field_names = [
+            "server",
+            "port",
+            "server_type",
+            "is_ssl",
+            "user",
+            "password",
+            "attach",
+            "original",
+        ]
+        fetchmail = self.env["fetchmail.server"].create({"name": "test_incoming"})
+        try:
+            with self.load_config(public=_incoming_config):
+                restore_env_managed_columns(self.env, "fetchmail.server", field_names)
+                table = self.env["fetchmail.server"]._table
+                for field_name in field_names:
+                    self.assertTrue(
+                        sql.column_exists(self.env.cr, table, field_name),
+                        f"Column {field_name} was not created",
+                    )
+                self.env.cr.execute(
+                    'SELECT server, port, server_type, is_ssl, "user",'
+                    " password, attach, original"
+                    " FROM fetchmail_server WHERE id = %s",
+                    [fetchmail.id],
+                )
+                row = self.env.cr.dictfetchone()
+                self.assertEqual(row["server"], "imap.example.com")
+                self.assertEqual(row["port"], 993)
+                self.assertEqual(row["server_type"], "imap")
+                self.assertTrue(row["is_ssl"])
+                self.assertEqual(row["user"], "imap_user")
+                self.assertEqual(row["password"], "imap_pass")
+                self.assertTrue(row["attach"])
+                self.assertFalse(row["original"])
+        finally:
+            self._drop_columns("fetchmail.server", field_names)
+
+    def test_restore_env_managed_columns_idempotent(self):
+        """Calling restore_env_managed_columns twice is safe and idempotent."""
+        field_names = ["smtp_host", "smtp_port"]
+        self.env["ir.mail_server"].create({"name": "test_idempotent"})
+        try:
+            with self.load_config(public=_outgoing_config):
+                restore_env_managed_columns(self.env, "ir.mail_server", field_names)
+                # Second call must not raise or corrupt data.
+                restore_env_managed_columns(self.env, "ir.mail_server", field_names)
+            table = self.env["ir.mail_server"]._table
+            for field_name in field_names:
+                self.assertTrue(sql.column_exists(self.env.cr, table, field_name))
+        finally:
+            self._drop_columns("ir.mail_server", field_names)
+
+    def test_restore_env_managed_columns_with_fallback_defaults(self):
+        """Fields with no value can be restored with fallback values
+        via field_defaults."""
+
+        field_names = ["smtp_host"]
+        server = self.env["ir.mail_server"].create({"name": "test_fallback"})
+        try:
+            # smtp_host has no config, no ORM default, and no env_default.
+            # With field_defaults, it should be populated with the fallback value.
+            restore_env_managed_columns(
+                self.env,
+                "ir.mail_server",
+                field_names,
+                field_defaults={"smtp_host": "fallback.example.com"},
+            )
+            table = self.env["ir.mail_server"]._table
+            column_exists = sql.column_exists(self.env.cr, table, "smtp_host")
+            self.assertTrue(column_exists)
+            self.env.cr.execute(
+                "SELECT smtp_host FROM ir_mail_server WHERE id = %s",
+                [server.id],
+            )
+            self.assertEqual(self.env.cr.fetchone()[0], "fallback.example.com")
+        finally:
+            self._drop_columns("ir.mail_server", field_names)
+
+    def test_restore_env_managed_columns_no_fallback(self):
+        """Fields with no value and no fallback are set to NULL."""
+
+        field_names = ["smtp_host"]
+        server = self.env["ir.mail_server"].create({"name": "test_no_value"})
+        try:
+            # smtp_host has no config, no default, and no field_defaults.
+            # The column should be created and set to NULL.
+            restore_env_managed_columns(self.env, "ir.mail_server", field_names)
+            table = self.env["ir.mail_server"]._table
+            column_exists = sql.column_exists(self.env.cr, table, "smtp_host")
+            self.assertTrue(column_exists)
+            self.env.cr.execute(
+                "SELECT smtp_host FROM ir_mail_server WHERE id = %s",
+                [server.id],
+            )
+            self.assertIsNone(self.env.cr.fetchone()[0])
+        finally:
+            self._drop_columns("ir.mail_server", field_names)
+
+    def test_restore_env_managed_columns_required_field_uses_model_default(self):
+        """Fields with no value can be restored from the model default (if available)
+        when no fallback is provided."""
+
+        field_names = ["smtp_authentication"]
+        server = self.env["ir.mail_server"].create({"name": "test_no_fallback"})
+        try:
+            # On supported Odoo versions smtp_authentication has a model default
+            # ('login'). Restoring without field_defaults should therefore succeed by
+            # using that effective value.
+            restore_env_managed_columns(self.env, "ir.mail_server", field_names)
+            self.env.cr.execute(
+                "SELECT smtp_authentication FROM ir_mail_server WHERE id = %s",
+                [server.id],
+            )
+            self.assertEqual(self.env.cr.fetchone()[0], "login")
+        finally:
+            # Manually drop in case the column was created.
+            model = self.env["ir.mail_server"]
+            if sql.column_exists(self.env.cr, model._table, "smtp_authentication"):
+                self.env.cr.execute(  # noqa: S608
+                    f'ALTER TABLE {model._table} DROP COLUMN "smtp_authentication"'
+                )