diff --git a/tempest/api/compute/admin/test_live_migration.py b/tempest/api/compute/admin/test_live_migration.py
index 72d5b18..ff84945 100644
--- a/tempest/api/compute/admin/test_live_migration.py
+++ b/tempest/api/compute/admin/test_live_migration.py
@@ -72,10 +72,9 @@
             block_migration = (CONF.compute_feature_enabled.
                                block_migration_for_live_migration and
                                not volume_backed)
-        body = self.admin_servers_client.live_migrate_server(
+        self.admin_servers_client.live_migrate_server(
             server_id, host=dest_host, block_migration=block_migration,
             **kwargs)
-        return body
 
     def _get_host_other_than(self, host):
         for target_host in self._get_compute_hostnames():
diff --git a/tempest/api/compute/test_live_block_migration_negative.py b/tempest/api/compute/test_live_block_migration_negative.py
index f072b81..7853962 100644
--- a/tempest/api/compute/test_live_block_migration_negative.py
+++ b/tempest/api/compute/test_live_block_migration_negative.py
@@ -37,10 +37,9 @@
 
     def _migrate_server_to(self, server_id, dest_host):
         bmflm = CONF.compute_feature_enabled.block_migration_for_live_migration
-        body = self.admin_servers_client.live_migrate_server(
+        self.admin_servers_client.live_migrate_server(
             server_id, host=dest_host, block_migration=bmflm,
             disk_over_commit=False)
-        return body
 
     @test.attr(type=['negative'])
     @test.idempotent_id('7fb7856e-ae92-44c9-861a-af62d7830bcb')
diff --git a/tempest/api/network/admin/test_negative_quotas.py b/tempest/api/network/admin/test_negative_quotas.py
index c256b5b..beb6ce6 100644
--- a/tempest/api/network/admin/test_negative_quotas.py
+++ b/tempest/api/network/admin/test_negative_quotas.py
@@ -57,8 +57,7 @@
         # Try to create a third network while the quota is two
         with self.assertRaisesRegex(
                 lib_exc.Conflict,
-                "An object with that identifier already exists\\n" +
-                "Details.*Quota exceeded for resources: \['network'\].*"):
+                "Quota exceeded for resources: \['network'\].*"):
             n3 = self.networks_client.create_network()
             self.addCleanup(self.networks_client.delete_network,
                             n3['network']['id'])
diff --git a/tempest/api/network/test_dhcp_ipv6.py b/tempest/api/network/test_dhcp_ipv6.py
index baf2b2e..3c96a93 100644
--- a/tempest/api/network/test_dhcp_ipv6.py
+++ b/tempest/api/network/test_dhcp_ipv6.py
@@ -338,7 +338,7 @@
                              {'subnet_id': subnet['id'],
                               'ip_address': ip}])
         self.assertRaisesRegex(lib_exc.Conflict,
-                               "object with that identifier already exists",
+                               "IpAddressAlreadyAllocated|IpAddressInUse",
                                self.create_port,
                                self.network,
                                fixed_ips=[{'subnet_id': subnet['id'],
diff --git a/tempest/api/object_storage/test_container_services_negative.py b/tempest/api/object_storage/test_container_services_negative.py
index f63c518..2856fab 100644
--- a/tempest/api/object_storage/test_container_services_negative.py
+++ b/tempest/api/object_storage/test_container_services_negative.py
@@ -173,5 +173,5 @@
         ex = self.assertRaises(exceptions.Conflict,
                                self.container_client.delete_container,
                                container_name)
-        self.assertIn('An object with that identifier already exists',
-                      str(ex))
+        self.assertIn('There was a conflict when trying to complete your '
+                      'request.', str(ex))
diff --git a/tempest/tests/negative/__init__.py b/tempest/tests/negative/__init__.py
deleted file mode 100644
index e69de29..0000000
--- a/tempest/tests/negative/__init__.py
+++ /dev/null