請問~關於版型出錯

* warning: unlink(files/css/7a7bed53d1433c068fcba56affdde769.css) [function.unlink]: Permission denied in /home/A9312031/public_html/drupal/includes/file.inc on line 468.
* warning: unlink(files/css/e0eb4f20b5991b9a63fabbab076c45a1.css) [function.unlink]: Permission denied in /home/A9312031/public_html/drupal/includes/file.inc on line 468.
* warning: unlink(files/css/6797ce0d824c14148d907588d517c54d.css) [function.unlink]: Permission denied in /home/A9312031/public_html/drupal/includes/file.inc on line 468.
* warning: unlink(files/css/d6208653b702d7cdbcfa6e77eb11bdc9.css) [function.unlink]: Permission denied in /home/A9312031/public_html/drupal/includes/file.inc on line 468.
* warning: unlink(files/css/9eb9107153acc422149b77012c13d3db.css) [function.unlink]: Permission denied in /home/A9312031/public_html/drupal/includes/file.inc on line 468.
* warning: unlink(files/css/3941385eb090953d8478f80c192b4c81.css) [function.unlink]: Permission denied in /home/A9312031/public_html/drupal/includes/file.inc on line 468.
* warning: unlink(files/css/576e9c15be643549a57deab4ccb083c7.css) [function.unlink]: Permission denied in /home/A9312031/public_html/drupal/includes/file.inc on line 468.
* warning: unlink(files/css/ad534f5128e895b692c42256132a5c54.css) [function.unlink]: Permission denied in /home/A9312031/public_html/drupal/includes/file.inc on line 468.

以上是小弟架好站之後，進到版型出現的錯誤訊息~
現在都無法更改版型，該怎麼辦呢？
請各位大大幫幫忙~
先謝謝各位先進^^