访问后台的时候自动补全了index.php并且报404错误，去掉index.php后可以正常访问

将此函数替换为

protected function _updatePathUseRewrites($url)

{

    if (!$this->getConfig(self::XML_PATH_USE_REWRITES) || !Mage::isInstalled()) {

        $indexFileName = $this->_isCustomEntryPoint() ? 'index.php' : basename($_SERVER['SCRIPT_FILENAME']);

        $url .= $indexFileName . '/';

    }

    return $url;

}