I think I might be encountering the same issue as cosmicgroove, so whoever helps us will be killing two birds with one stone. This is the error message I received:
Error establishing a database connection
This either means that the username and password information in your wp-config.php file is incorrect or we can’t contact the database server at localhost. This could mean your host’s database server is down.
* Are you sure you have the correct username and password?
* Are you sure that you have typed the correct hostname?
* Are you sure that the database server is running?
If you’re unsure what these terms mean you should probably contact your host. If you still need help you can always visit the WordPress Support Forums.
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And this is not the first time I’ve done this. I copied and pasted the username, hostname, db name and checked to make sure the password was absolutely correct. The database server isn’t down because I checked it several times throughout the day.
What could possibly be the issue?