diff --git a/locales/en.json b/locales/en.json
index 84a01dfaa..75912cab5 100644
--- a/locales/en.json
+++ b/locales/en.json
@@ -285,7 +285,9 @@
     "domain_dyndns_already_subscribed": "You have already subscribed to a DynDNS domain",
     "domain_dyndns_root_unknown": "Unknown DynDNS root domain",
     "domain_exists": "The domain already exists",
+    "domain_property_unknown": "The property {property} dooesn't exist",
     "domain_hostname_failed": "Unable to set new hostname. This might cause an issue later (it might be fine).",
+    "domain_registrar_unknown": "This registrar is unknown. Look for yours with the command `yunohost domain catalog`",
     "domain_remove_confirm_apps_removal": "Removing this domain will remove those applications:\n{apps}\n\nAre you sure you want to do that? [{answers}]",
     "domain_uninstall_app_first": "Those applications are still installed on your domain:\n{apps}\n\nPlease uninstall them using 'yunohost app remove the_app_id' or move them to another domain using 'yunohost app change-url the_app_id' before proceeding to domain removal",
     "domain_name_unknown": "Domain '{domain}' unknown",
@@ -528,6 +530,7 @@
     "regenconf_need_to_explicitly_specify_ssh": "The ssh configuration has been manually modified, but you need to explicitly specify category 'ssh' with --force to actually apply the changes.",
     "regex_incompatible_with_tile": "/!\\ Packagers! Permission '{permission}' has show_tile set to 'true' and you therefore cannot define a regex URL as the main URL",
     "regex_with_only_domain": "You can't use a regex for domain, only for path",
+    "registrar_is_not_set": "The registrar for this domain has not been configured",
     "restore_already_installed_app": "An app with the ID '{app:s}' is already installed",
     "restore_already_installed_apps": "The following apps can't be restored because they are already installed: {apps}",
     "restore_backup_too_old": "This backup archive can not be restored because it comes from a too-old YunoHost version.",
diff --git a/src/yunohost/domain.py b/src/yunohost/domain.py
index 920df934f..6c90b533e 100644
--- a/src/yunohost/domain.py
+++ b/src/yunohost/domain.py
@@ -809,7 +809,7 @@ def domain_setting(domain, key, value=None, delete=False):
     # GET
     if value is None and not delete:
         if not key in domain_settings:
-            raise YunohostValidationError("This key doesn't exist!")
+            raise YunohostValidationError("domain_property_unknown", property=key)
 
         return domain_settings[key]
 
@@ -827,11 +827,10 @@ def domain_setting(domain, key, value=None, delete=False):
                 ttl = int(value)
             except ValueError:
                 # TODO add locales
-                raise YunohostError("bad_value_type", value_type=type(ttl))
+                raise YunohostError("invalid_number", value_type=type(ttl))
 
             if ttl < 0:
-                # TODO add locales
-                raise YunohostError("must_be_positive", value_type=type(ttl))
+                raise YunohostError("pattern_positive_number", value_type=type(ttl))
         domain_settings[key] = value
         _set_domain_settings(domain, domain_settings)
 
@@ -900,7 +899,7 @@ def domain_registrar_info(domain):
     registrar_info = _load_registrar_setting(dns_zone)
     if not registrar_info:
         # TODO add locales
-        raise YunohostError("no_registrar_set_for_this_dns_zone", dns_zone=dns_zone)
+        raise YunohostError("registrar_is_not_set", dns_zone=dns_zone)
     
     logger.info("Registrar name: " + registrar_info['name'])
     for option_key, option_value in registrar_info['options'].items():
@@ -924,7 +923,7 @@ def domain_registrar_set(domain, registrar, args):
     registrars = yaml.load(open(REGISTRAR_LIST_PATH, "r+"))
     if not registrar in registrars.keys():
         # FIXME créer l'erreur
-        raise YunohostError("registrar_unknown")
+        raise YunohostError("domain_registrar_unknown")
 
     parameters = registrars[registrar]
     ask_args = []