Error with sitemap_index.xml

I get the below error when trying to access the sitemap file.... Does anyone have any idea how to fix this?

http://www.ajia.im/sitemap_index.xml
Error loading stylesheet: An unknown error has occurred (805303f4)http://www.cardfun.com.au/ajia.im/wp...itemap-xsl.php

Not sure if it makes a difference but I am using Yoast's SEO plugin.

 

Loon in your wordpress plugin plugin folder for the file below and edit sitemap-core.php:
Full path : /wp-content/plugins/google-sitemap-generator/sitemap-core.php

Find the following code :
function GetPluginUrl() {
//Try to use WP API if possible, introduced in WP 2.6
if (function_exists('plugins_url')) return trailingslashit(plugins_url(basename(dirname(__FILE__))));
//Try to find manually... can't work if wp-content was renamed or is redirected
$path = dirname(__FILE__);
$path = str_replace("\\","/",$path);
$path = trailingslashit(get_bloginfo('wpurl')) . trailingslashit(substr($path,strpos($path,"wp-content/")));
return $path;
}

And REPLACE it with this:
function GetPluginUrl() {
//if (function_exists('plugins_url')) return trailingslashit(plugins_url(basename(dirname(__FILE__))));
$path = dirname(__FILE__);
$path = str_replace("\\","/",$path);
//$path = trailingslashit(get_bloginfo('wpurl')) . trailingslashit(substr($path,strpos($path,"wp-content/")));
$path = trailingslashit(substr($path,strpos($path,"wp-content/")));
return $path;
}

 

I saw that fix on other forums but the problem is that I don't have a google-sitemap-generator folder...

in /wp-content/plugins/
I have the folers akismet, robots-meta, wordpress-importer, wordpress-seo, wp-ban, wti-like-post

and the files index.php and hello.php