请确保下面的文件是可写的:

/path/to/your/magento-install
/path/to/your/magento-install/downloader
/path/to/your/magento-install/downloader/config.ini
/path/to/your/magento-install/downloader/pearlib/config.ini
/path/to/your/magento-install/downloader/pearlib/pear.ini
/path/to/your/magento-install/downloader/pearlib/php