Wp super Cache issue

Hello when i installed wp super cache on my blog i get this error in html view source code:

<!-- WP Super Cache is installed but broken. The path to wp-cache-phase1.php in wp-content/advanced-cache.php must be fixed! -->

i have read the readme file but as far as i know i have done everything correct, the script is located under: wp-content/mu-plugins/wp-super-cache/

wp-cache.php is located under: wp-content/mu-plugins/
advanced-cache.php is located under: wp-content/

any ideas on what could be wrong?