Your php script can't connect to the database. Open the file db.inc.php and make sure that the server name (usually localhost), database name, database username, and database password are all correct.
Before you start cooking up PHP, ASP, PERL or other scripts I highly recommend making sure your User Access to your database is viable. To the point use MySQL Administrator or MySQL QueryBrowers or if you prefer the cmd line you can use mysql.exe
Make sure the Users have been GRANT'd access for the DATABASE on the HOST you are planning on using. For example, if you have a user called dbuser that needs to root access to database Maximus from host woobie you would need to:
GRANT ALL ON maximus.* TO dbuser@woobie IDENTIFIED by 'password'
Now if ol' dbuser is a shared access account that say can be used on multiple client computers you should wildcard the host. Thus a SQL statement like:
GRANT SELECT, INSERT, UPDATE, DELETE on maximus.* TO dbuser@'%' IDENTIFIED BY 'password'
Your case is probably related to the user name not being allowed to access the database from the host you are running the app. Thus revisit the user accounts and you should be able to trace it back from there. Note - I would definitly use a tool like MySQL Query Browser to validate the user logins and capabilities BEFORE I started applying scripts.
