mod_rewrite and Mac OS X Personal Web Sharing
It was very frustrating installing a fresh Wordpress on my Mac and finding that the permalinks didn’t work. Turns out the default Apache settings for personal web sharing on OS X disable .htaccess overriding.
sudo mate /etc/httpd/users/yourusername.conf
Now you’ll want to enable Apache to follow symbolic links:
Options Indexes MultiViews FollowSymLinks
And to allow .htaccess overriding:
AllowOverride All
The file should then look like:
<Directory "/Users/yourusername/Sites/">
    Options Indexes MultiViews FollowSymLinks
    AllowOverride All
    Order allow,deny
    Allow from all
</Directory>
Now in System Preferences, stop and start ‘Personal Web Sharing’. Things should work perfectly now.
