WordPress : can't find wp-load.php file

This is probably a simple problem, but can't figure it out...

1) I installed the wordpress file directly under the xxxx directory; wp-admin, wp-content, wp-includes are all within wordpress file.

2) wp-load.php exists wordpress folder, I copied it into the wp-admin folder as well.

3) wp-config.php exists in wordpress folder.

the errors are as follows:

<br />
<b>Warning</b>:  require_once(../wp-load.php): failed to open stream: No such file or directory in <b>D:\xampp\htdocs\dev\wp-content\plugins\workflow\ajax.php</b> on line <b>6</b><br />
<br />
<b>Fatal error</b>:  require_once(): Failed opening required '../wp-load.php' (include_path='D:\xampp\php\PEAR') in <b>D:\xampp\htdocs\dev\wp-content\plugins\workflow\ajax.php</b> on line <b>6</b><br />

This problem is in plugin folder.

and i add this code in php file :-

if ( defined('ABSPATH') )
require_once(ABSPATH . 'wp-load.php');
else
require_once('../wp-load.php');

via Chebli Mohamed