3 files changed, 8 insertions, 8 deletions
diff --git a/phpBB/includes/db/migration/tool/config.php b/phpBB/includes/db/migration/tool/config.php
index 458a25fb66..0b626bf455 100644
--- a/phpBB/includes/db/migration/tool/config.php
+++ b/phpBB/includes/db/migration/tool/config.php
@@ -49,7 +49,7 @@ class phpbb_db_migration_tool_config implements phpbb_db_migration_tool_interfac
 	{
 		if (isset($this->config[$config_name]))
 		{
-			throw new phpbb_db_migration_exception('CONFIG_ALREADY_EXIST', $config_name);
+			return;
 		}
 
 		$this->config->set($config_name, $config_value, !$is_dynamic);
@@ -105,7 +105,7 @@ class phpbb_db_migration_tool_config implements phpbb_db_migration_tool_interfac
 	{
 		if (!isset($this->config[$config_name]))
 		{
-			throw new phpbb_db_migration_exception('CONFIG_NOT_EXIST', $config_name);
+			return;
 		}
 
 		$this->config->delete($config_name);
diff --git a/phpBB/includes/db/migration/tool/module.php b/phpBB/includes/db/migration/tool/module.php
index ad94c5aadb..ec683d36af 100644
--- a/phpBB/includes/db/migration/tool/module.php
+++ b/phpBB/includes/db/migration/tool/module.php
@@ -236,7 +236,7 @@ class phpbb_db_migration_tool_module implements phpbb_db_migration_tool_interfac
 
 		if ($this->exists($class, $parent, $data['module_langname']))
 		{
-			throw new phpbb_db_migration_exception('MODULE_ALREADY_EXIST', $data['module_langname']);
+			return;
 		}
 
 		if (!class_exists('acp_modules'))
@@ -369,7 +369,7 @@ class phpbb_db_migration_tool_module implements phpbb_db_migration_tool_interfac
 		{
 			if (!$this->exists($class, $parent, $module))
 			{
-				throw new phpbb_db_migration_exception('MODULE_NOT_EXIST', ((isset($this->user->lang[$module])) ? $this->user->lang[$module] : $module));
+				return;
 			}
 
 			$parent_sql = '';
@@ -442,7 +442,7 @@ class phpbb_db_migration_tool_module implements phpbb_db_migration_tool_interfac
 				$result = $acp_modules->delete_module($module_id);
 				if (!empty($result))
 				{
-					throw new phpbb_db_migration_exception('MODULE_NOT_REMOVABLE', $module_id, $result);
+					return;
 				}
 			}
 
diff --git a/phpBB/includes/db/migration/tool/permission.php b/phpBB/includes/db/migration/tool/permission.php
index 4231fbe1dd..3b196fdbc2 100644
--- a/phpBB/includes/db/migration/tool/permission.php
+++ b/phpBB/includes/db/migration/tool/permission.php
@@ -107,7 +107,7 @@ class phpbb_db_migration_tool_permission implements phpbb_db_migration_tool_inte
 	{
 		if ($this->exists($auth_option, $global))
 		{
-			throw new phpbb_db_migration_exception('PERMISSION_ALREADY_EXIST', $auth_option);
+			return;
 		}
 
 		// We've added permissions, so set to true to notify the user.
@@ -190,7 +190,7 @@ class phpbb_db_migration_tool_permission implements phpbb_db_migration_tool_inte
 	{
 		if (!$this->exists($auth_option, $global))
 		{
-			throw new phpbb_db_migration_exception('PERMISSION_NOT_EXIST', $auth_option);
+			return;
 		}
 
 		if ($global)
@@ -315,7 +315,7 @@ class phpbb_db_migration_tool_permission implements phpbb_db_migration_tool_inte
 
 		if (!$role_id)
 		{
-			throw new phpbb_db_migration_exception('ROLE_NOT_EXIST', $role_name);
+			return;
 		}
 
 		$sql = 'DELETE FROM ' . ACL_ROLES_DATA_TABLE . '