把全部文件和资料庫文件從本機上傳到虛擬伺服器後，出現drupal的Site off-line畫面：
The site is currently not available due to technical problems. Please try again later. Thank you for your understanding.
If you are the maintainer of this site, please check your database settings in the settings.php file and ensure that your hosting provider's database server is running. For more help, see the handbook, or contact your hosting provider.
The mysql error was: Access denied for user ''@'localhost' (using password: YES).
settings.php裏面已經設定了$db_url = 'mysql://和$base_url 。$db_prefix = ''也需要設定嗎？還需要修改settings.php的哪些地方？
已清除全部cookies，刪除default.settings.php也試過，在FTP中改變settings.php的權限644、755或777也試過，都沒成功。
請問應怎樣解決？
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謝謝。問題已解決，我放的空間不能使用localhost。