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Whoa... Please next time before you try to undertake something you're not familiar with, do a little research in advance. This question has been answered MANY times before in these forums, so a little search would have wielded a wealth of information. And tone down a little on the demanding tone, we're all trying to help you
Anyways, what you need to do EXACTLY, is download the mainfile.php file from your server, open it in your fav text editor, and make sure that the database servername, database username, database user password and database name are absolutely correct. You should have these values provided by your hosting provider. Make sure that it is correctly spelled, that the servername has NO trailing slash, and that the usernames and passwords are case sensitive. When you have corrected this, save, upload to your server, overwriting the defect mainfile.php, make sure it is set to read-only (chmod 444), and reload your site by going to your sites URL.
Herko
