I’ve had this same “Error establishing a database connection” problem and finally solved it with the help found at
https://www.ads-software.com/support/topic/59700
In the wp-config.php file I’ve changed the line:
define(‘DB_HOST’, ‘localhost’);
by:
define(‘DB_HOST’, ‘127.0.0.1’);
and it worked!!!
thanks a lot to the WordPress support!
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