When a MySQL client keeps rejecting your login, it usually points to user authentication problems. A frequent message users see is error 1045 (28000): Access Denied for User, indicating that the database server doesn’t recognize the credentials you provided. This guide walks you through simple ways to confirm your username and password, update user privileges, and make sure the credentials are allowed to connect from your host. It also covers how to use safe mode or reset commands when you have lost administrative access. With clear steps and examples, even someone new to databases can fix common authentication issues and regain control of their MySQL server.