diff --git a/server/registration/mutations_public.py b/server/registration/mutations_public.py
index 7119d0a3..156bf918 100644
--- a/server/registration/mutations_public.py
+++ b/server/registration/mutations_public.py
@@ -59,8 +59,7 @@ class Registration(relay.ClientIDMutation):
     def return_registration_msg(cls, message):
         # even if the user has no valid license treat it like a success
         if message == UNKNOWN_ERROR:
-            error = RegistrationError(field=message)
-            return cls(success=False, errors=[error], message='')
+            raise Exception(message)
 
         return cls(success=True, errors=[], message=message)
 
diff --git a/server/users/mutations_public.py b/server/users/mutations_public.py
index ac52c43e..065d2574 100644
--- a/server/users/mutations_public.py
+++ b/server/users/mutations_public.py
@@ -37,12 +37,12 @@ class LocalLogin(relay.ClientIDMutation):
             username = kwargs.get('username_input')
             user = authenticate(username=username, password=password)
             if user is None:
-                return cls(success=False, errors=[{'field': 'invalid_credentials'}], message='')
+                raise Exception('invalid_credentials')
             login(info.context, user)
 
             return cls(success=True, errors=[], message='')
 
-        return cls(success=False, errors=[{'field': 'not_implemented'}], message='')
+        raise Exception('not_implemented')
 
 
 class Login(relay.ClientIDMutation):
@@ -80,8 +80,7 @@ class Login(relay.ClientIDMutation):
     @classmethod
     def return_login_message(cls, message):
         if message == EMAIL_NOT_VERIFIED or message == UNKNOWN_ERROR or message == 'invalid_credentials':
-            error = LoginError(field=message)
-            return cls(success=False, errors=[error], message='')
+            raise Exception(message)
         return cls(success=True, errors=[], message=message)
 
 
diff --git a/server/users/tests/test_local_login.py b/server/users/tests/test_local_login.py
index c6af9227..ce07aabb 100644
--- a/server/users/tests/test_local_login.py
+++ b/server/users/tests/test_local_login.py
@@ -63,5 +63,5 @@ class LocalLoginTests(TestCase):
         self.user.save()
 
         result = self.make_login_mutation(self.user.email, 'test1234')
-        self.assertFalse(result.get('data').get('localLogin').get('success'))
+        self.assertEqual(result.get('errors')[0].get('message'), 'invalid_credentials')
 
diff --git a/server/users/tests/test_login.py b/server/users/tests/test_login.py
index 3703a4c4..29ac9cd6 100644
--- a/server/users/tests/test_login.py
+++ b/server/users/tests/test_login.py
@@ -183,8 +183,7 @@ class LoginTests(TestCase):
     def test_user_with_no_login_cannot_login(self, post_mock):
         result = self.make_login_mutation('some')
 
-        self.assertFalse(result.get('data').get('login').get('success'))
-        self.assertEqual(result.get('data').get('login').get('errors')[0].get('field'), 'invalid_credentials')
+        self.assertEqual(result.get('errors')[0].get('message'), 'invalid_credentials')
 
     @patch.object(HepClient, 'is_email_verified', return_value=False)
     @patch.object(HepClient, 'customer_me', return_value=ME_DATA)
@@ -192,9 +191,7 @@ class LoginTests(TestCase):
         result = self.make_login_mutation(TOKEN)
 
         User.objects.get(email=ME_DATA['email'])
-
-        self.assertFalse(result.get('data').get('login').get('success'))
-        self.assertEqual(result.get('data').get('login').get('errors')[0].get('field'), 'email_not_verified')
+        self.assertEqual(result.get('errors')[0].get('message'), 'email_not_verified')
 
     @patch.object(HepClient, 'myskillbox_product_for_customer', return_value=None)
     @patch.object(HepClient, 'customer_me', return_value=ME_DATA)
@@ -224,12 +221,10 @@ class LoginTests(TestCase):
     def test_user_can_login_with_unconfirmed_email(self, me_mock):
         result = self.make_login_mutation(TOKEN)
 
-        self.assertFalse(result.get('data').get('login').get('success'))
-        self.assertEqual(result.get('data').get('login').get('errors')[0].get('field'), 'email_not_verified')
+        self.assertEqual(result.get('errors')[0].get('message'), 'email_not_verified')
 
     @patch.object(requests, 'get', return_value=MockResponse(500))
     def test_user_gets_notified_if_server_error(self, post_mock):
         result = self.make_login_mutation(TOKEN)
 
-        self.assertFalse(result.get('data').get('login').get('success'))
-        self.assertEqual(result.get('data').get('login').get('errors')[0].get('field'), 'unknown_error')
+        self.assertEqual(result.get('errors')[0].get('message'), 'unknown_error')