Hi, you can put this in your index.php or header.php file (depends where you have the <head …> … </head> stuff):
<?php
$basehref = "http://".$_SERVER['SERVER_NAME'].($_SERVER['SCRIPT_NAME']);
?>
<base href="<?php echo"$basehref"; ?>">
It works when your main index.php file is in the same directory as the entire wp install.