wordpress首頁打開出現(xiàn)下載

我的wordpress博客在打開首頁時無法顯示，會出現(xiàn)下載一個這樣的文檔：

<?php
/**
 * Front to the WordPress application. This file doesn't do anything, but loads
 * wp-blog-header.php which does and tells WordPress to load the theme.
 *
 * @package WordPress
 */

/**
 * Tells WordPress to load the WordPress theme and output it.
 *
 * @var bool
 */
define('WP_USE_THEMES', true);

/** Loads the WordPress Environment and Template */
require( dirname( __FILE__ ) . '/wp-blog-header.php' );

其他頁面都是正常的，后臺也能正常進(jìn)入。請問應(yīng)當(dāng)如何解決？