Adding wordpress to files outside the root

Blog:
http://www.example.com/index.php
/about/
http://www.example.com/about/index.php
path:
require(‘../wp-blog-header.php’);

Blog:
http://www.example.com/blog/index.php
/about/
http://www.example.com/about/index.php
path:
require(‘../../blog/wp-blog-header.php’);

It’s early, and I’m not entirely sure about the second part there. It’s the ‘../’ that needs adjusting if anything.

Another way is this.
Go look at Options > Misc, and the top items there are the file path for image uploads. Change the end of that to point directly at wp-blog-header and use a full path instead of a relative path.

I’d try:

require(‘../wp-blog-header.php’);

with as many ../ as you need to complete the relative path to the WordPress file.