求重新装新的DRUPAL +重新创建数据库 （怎样删除重装一遍。)

我现在想删除我的WEB SITE & MYSQL 数据库都在本地服务器上面，但是仍然出现下面的错误。
请教如何删除本地站点和数据库，重新建立一套而没有下面的影响。在线等待。。。

测试安装后发现问题，重新装新的DRUPAL 是出现仍然链接原来数据库的问题（如下）。
后来删除了IIS 上面的WEB SITE 和删除MYSQL 数据库后，重建后仍然链接原来的数据库，希望帮助我.
在哪里修改才能解决。谢谢

Unable to select database
We were able to connect to the MySQL database server (which means your username and password are okay) but not able to select the database.

The MySQL error was: Unknown database 'drupal6'.

Currently, the database is drupal6. The username is root and the database server is localhost.

Are you sure you have the correct database name?
Are you sure the database exists?
Are you sure the username has permission to access the database?
For more help, see the Installation and upgrading handbook. If you are unsure what these terms mean you should probably contact your hosting provider.