wp-config.php corrupt

Hi all,

I made a wp site online, works perfect but suddenly on opening, the site again askes to make a new configuration file.

This is what I tried:
1. I downloaded the file (ftp) and opened it with dreamweaver. Seems ok.
2. I uploaded the original wp-config.php file wtih the SQL settings, including the prefix.

This does not wordk. When I try to open the site, it keeps telling me that there is no wp-config.php file.

Can I fix this?

Thanks