Connection issues at start...error message

[toplisek]

I have put correct db,password and username.
As I had to change all tables in previous installation to Uni code I Installed again forum files.
Need urgent reply as I did nto know that at the start I will have issues.

How to avoid error such us:
Step 2) Connect to the database
Attempting to attach to database
Error description: mysqli_real_connect() [function.mysqli-real-connect]: (28000/1045): Access denied for user 'root'@'localhost' (using password: NO) /home/borelbs/public_html//forum/install/includes/class_core.php on line 1138
The database has failed to connect because you do not have permission to connect to the server. Please confirm the values entered in the 'includes/config.php' file.

[Trevor Hannant]

Check in your server control panel or with your host that the database user has the correcy permissions.

[toplisek]

Yes what permission is correct. Can you be more specific....

[Trevor Hannant]

Access denied for user 'root'@'localhost'

If the database user 'root' is being denied access, then check the permissions assigned to 'root'.

[toplisek]

Check the permissions assigned to 'root'.
Where to see or only Hosting can check this?

[toplisek]

I have PHP 5.2.6 but maybe there is error because of MYSQLi.

Is this working always?