ithyn

DB_HOST refers to where the MySQL server resides. For most hosting companies, you can put “localhost” (without quotes) into the DB_HOST field.

If localhost doesn’t work for you, contact your hosting support and they should be able to quickly tell you.

You can do a manual upgrade. Download the WordPress files and upload them to your server via FTP. No need to go in through the WordPress control panel.

You’ve got to place that code (plus more code for printing the categories) in the functions.php file of your theme. Basically, create a widget, then place that widget on your sidebar via WordPress.

It depends on your server setup. Check this link for more info.

Your php.ini file is also a good place to check. That may show you where the server is set up to push errors to.

Check your PHP error logs. Typically, blank screens are a symptom of PHP running into errors somewhere.

You need to go to wordpress.com, not your personal blog.

Use the get_categories function (see here for more info):

$categories = get_categories('order_by=name');

Edit your profile on wordpress.com (this requires going to wordpress.com and creating an account).

When you edit your profile, you should see a printed line right at the top of the screen that contains your API key.

All at once? Easiest way is to get access to the MySQL database using PHPMyAdmin or a similar application.

In WordPress, you can see IDs by looking in your address bar when you have a post/page open in the editor.

Also, you may look at the theme you are using. If the theme has not included the byline, then it won’t show up.

What Web site are you using? Did you create an account on wordpress.com or elsewhere?