Not sure if this is the case in dreamhost, but in most hosts, you need to “attach” or “assign” the db user to the db in cpanel. If you ahve not done this, you will get the error you describe. http://www.wpwhitesecurity.com/wordpress-tutorial/wordpress-database-cpanel/
Can’t Install WordPress (local) Failed to open file wp-includes/wp-db.php
If you need a processing endpoint with access to the WordPress API, use the admin_post_ action and eliminate the need to manually include wp-config.php or any other WordPress files. // add for logged-in visitors add_action( ‘admin_post_your_action’, ‘prefix_your_action_function’ ); // for non logged-in visitors add_action( ‘admin_post_nopriv_your_action’, ‘prefix_your_action_function’ ); function prefix_your_action_function() { global $wpdb; // your processing … Read more
Although there’s no sign of any support currently for named pipes in WordPress, Ticket #32798 on the WordPress Trac added functionality for using named pipes under Windows. However, because it awaits review, it is not currently part of the WordPress Software, nor is it supported.
We you want to customise your Error Establishing Database Connection to something else then you need to create a file. Here is the documentation for that https://yoast.com/custom-wordpress-database-error-pages/
In this case, I had to reset the some of the file permissions of the WP install to 775. The the fault was with the managed hosting provider having this problem with many of their multisite installs.
It is not absolutely necessary to add anything to the config file. However it’s a good idea to do a test to look for any unsecured Http calls, such as stylesheets or Scripts. A good resource for this is https://www.whynopadlock.com/. The force SSL Setting can sometimes help with requests coming from plug-ins or anything you … Read more
Have you set the constants WP_CONTENT_FOLDERNAME and WP_CONTENT_DIR ? If not, that’s likely to be your problem.
I changed the password for the database user of my website, updated wp-config.php and wordpress asks to be reinstalled
A database error can occur for many reasons. It’s usually the result of an incorrect database address, username, or password. It’s likely not a timeout failure, since WordPress has a separate error for that. Here are two common issues: DB Configuration Since you have intermittent failures, this likely points to an issue with the database … Read more