在php中获取ftp_get()的警告

我尝试使用ftp_get()检索文本文件 当我执行脚本时,会收到警告:

ftp_get() [function.ftp-get]: Can't open data connection

有人能告诉我们出了什么问题吗?自从我移动到以前的主机/服务器时,它就坏了。是否有一些特定的PHP配置。我检查了phpinfo并启用了ftp支持。 连接通过cuteftp获得资源ID和用户名、密码和ftp主机。

function _getFtpFile( $fileName = '' ) {
    if($fileName == '') {
        return false;
    }

    $model = $this->getModel();
    $params =& $model->getParams();

    $vebraHost = $params->get('vebra_host');
    $vebraUser = $params->get('vebra_username');
    $vebraPass = $params->get('vebra_password');
    $localFile = JPATH_BASE.'/tmp/tmp.csv';

    // Delete the file in case it exists
    @unlink($localFile);

    // set up basic connection
    $connId = ftp_connect($vebraHost);

    // login with username and password
    $loginResult = ftp_login($connId, $vebraUser, $vebraPass);

    // turn on passive mode transfers
    ftp_pasv($connId, true);

    // try to download $server_file and save to $localFile
    if (!ftp_get($connId, $localFile, $fileName, FTP_BINARY)) {
        $file = false;
    } else {
        $file = $localFile;
    }

    // close the connection
    ftp_close($connId);

    return $file;
}