diff --git a/addons/website_mail_channel/controllers/main.py b/addons/website_mail_channel/controllers/main.py
index 4a9e2c449a8..3aa9491bf54 100644
--- a/addons/website_mail_channel/controllers/main.py
+++ b/addons/website_mail_channel/controllers/main.py
@@ -228,15 +228,19 @@ class MailGroup(http.Controller):
     def confirm_unsubscribe(self, channel, partner_id, token, **kw):
         subscriber = request.env['mail.channel.partner'].search([('channel_id', '=', channel.id), ('partner_id', '=', partner_id)])
         if not subscriber:
+            partner = request.env['res.partner'].browse(partner_id).sudo().exists()
             # FIXME: remove try/except in master
             try:
-                return request.render(
-                    'website_mail_channel.not_subscribed', {
-                    'partner_id': partner_id
-                })
+                response = request.render(
+                    'website_mail_channel.not_subscribed',
+                    {'partner_id': partner})
+                # make sure the rendering (and thus error if template is
+                # missing) happens inside the try block
+                response.flatten()
+                return response
             except ValueError:
                 return _("The address %s is already unsubscribed or was never subscribed to any mailing list") % (
-                    partner_id.email
+                    partner.email
                 )
 
         subscriber_token = channel._generate_action_token(partner_id, action='unsubscribe')
diff --git a/addons/website_mail_channel/tests/__init__.py b/addons/website_mail_channel/tests/__init__.py
new file mode 100644
index 00000000000..2e3364d701d
--- /dev/null
+++ b/addons/website_mail_channel/tests/__init__.py
@@ -0,0 +1,2 @@
+# -*- coding: utf-8 -*-
+from . import test_unsubscribe
diff --git a/addons/website_mail_channel/tests/test_unsubscribe.py b/addons/website_mail_channel/tests/test_unsubscribe.py
new file mode 100644
index 00000000000..44128c30b86
--- /dev/null
+++ b/addons/website_mail_channel/tests/test_unsubscribe.py
@@ -0,0 +1,71 @@
+# -*- coding: utf-8 -*-
+import requests
+
+from odoo.api import Environment
+from odoo.tests import common
+from odoo.tools.misc import mute_logger
+
+
+class TestConfirmUnsubscribe(common.HttpCase):
+    def setUp(self):
+        super(TestConfirmUnsubscribe, self).setUp()
+
+        cr = self.registry.cursor()
+        # apparently HttpCase does not properly update self.env?
+        self.env2 = env = Environment(cr, self.uid, {})
+        self.partner = env['res.partner'].create({
+            'name': 'Bob',
+            'email': 'bob@bob.bob'
+        })
+        self.mailing_list = env['mail.channel'].create({
+            'name': 'Test Mailing List',
+            'public': 'public',
+        })
+        self.token = self.mailing_list._generate_action_token(self.partner.id, action='unsubscribe')
+
+    def test_not_subscribed(self):
+        """Test warning works"""
+        self.env2.cr.release()
+
+        self._unsubscribe_check("The address %s is already unsubscribed" % self.partner.email)
+
+    @mute_logger('odoo.addons.website.models.ir_ui_view')
+    def test_not_subscribed_no_template(self):
+        """ Test warning works on db without template (code update w/o module update) """
+        self.env2.ref('website_mail_channel.not_subscribed').unlink()
+        self.assertEquals(
+            self.env2['ir.model.data'].search_count([
+            ('module', '=', 'website_mail_channel'),
+            ('name', '=', 'not_subscribed'),
+        ]), 0, 'XID for template should have been deleted')
+        self.env2.cr.release()
+
+        self._unsubscribe_check("The address %s is already unsubscribed or was never subscribed to any mailing list" % self.partner.email)
+
+    def test_wrong_token(self):
+        self.mailing_list.sudo().write({
+            'channel_partner_ids': [(4, self.partner.id, False)]
+        })
+        self.env2.cr.release()
+        self.token = 'XXX'
+
+        self._unsubscribe_check("Invalid or expired confirmation link.")
+
+    def test_successful_unsubscribe(self):
+        self.mailing_list.sudo().write({
+            'channel_partner_ids': [(4, self.partner.id, False)]
+        })
+        self.env2.cr.release()
+
+        self._unsubscribe_check("You have been correctly unsubscribed")
+
+    def _unsubscribe_check(self, text):
+        url = "/groups/unsubscribe/{}/{}/{}".format(
+            self.mailing_list.id, self.partner.id,
+            self.token
+        )
+        # FIXME: may need to be altered during 11.0 forward port
+        r = self.url_open(url)
+        body = r.read().decode('utf-8')
+        # normalize space to make matching simpler
+        self.assertIn(text, u' '.join(body.split()))