If you are running WordPress 2.0.2 and have enabled permalinks, you may have had problems creating a new category or page to your site. I recently encountered this dilemma and devised the following strategy for adding, editing, or even deleting WordPress categories and pages. Note: this tutorial assumes you are running Apache.
wp-includes/vars.php and find (around line #39):
$is_apache = ( strstr($_SERVER['SERVER_SOFTWARE'], 'Apache') || strstr($_SERVER['SERVER_SOFTWARE'], 'LiteSpeed') ) ? 1 : 0;
Comment out that line and add the following:
$is_apache = 1;
Save the file and upload it to your server.
Next, check the file attributes of your htaccess file(s). Ensure that the file is writable with a setting of either
666 or even
777 (or whatever works best on your server).
Finally, create or edit the necessary category or categories, publish a post or two under the new/edited category, and then double-check that everything is working as expected.
Now that you are a big winner with your new category, be sure to change the htaccess file permissions back to
644 or equivalent. Also, comment out the new line in the
vars.php file and uncomment out (i.e., comment in) the original line of code.