This error is usually fixed by double checking what the three questions ask on the WordPress installation error page.
WordPress Install Error
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 [...]

The more recent versions of the popular blogging platform WordPress have been giving errors when trying to upload a file through the WordPress admin. The two most common errors seem to be “Unable to create directory” and “The uploaded file could not be moved to”. To fix these errors try this:
Unable to create directory …
Set [...]

Designing websites with CSS or cascading style sheets can provide advantages in allowing search engines to index your site more easily. It also gives web designers a nice, clean way to organize and format content. In this example, I show how to use CSS to use lists to organize and style vertical navigation.