diff --git a/addons/mail/models/res_users.py b/addons/mail/models/res_users.py
index 469b996ca19..30b44080ebb 100644
--- a/addons/mail/models/res_users.py
+++ b/addons/mail/models/res_users.py
@@ -277,16 +277,16 @@ class Users(models.Model):
             )
 
         if post.get('request_blacklist'):
-            users_to_blacklist = self.filtered(
-                lambda user: tools.email_normalize(user.email))
+            users_to_blacklist = [(user, user.email) for user in self.filtered(
+                lambda user: tools.email_normalize(user.email))]
         else:
             users_to_blacklist = []
 
         super(Users, self)._deactivate_portal_user(**post)
 
-        for user in users_to_blacklist:
+        for user, user_email in users_to_blacklist:
             self.env['mail.blacklist']._add(
-                user.email,
+                user_email,
                 message=_('Blocked by deletion of portal account %(portal_user_name)s by %(user_name)s (#%(user_id)s)',
                           user_name=current_user.name, user_id=current_user.id,
                           portal_user_name=user.name)