文件上传(工作在本地，但不能在远程服务器上)

我试图通过HTML表单将文件(msword/doc)上传到Apache服务器文件夹。当我在本地进行测试时(我通过MAMP进行测试)，它可以工作，但是当我将它上传到远程服务器(例如GoDaddy)时，它不起作用。它显示"文件上传有问题"。

下面是处理文件上传的代码片段。我不知道我的条件句出了什么问题。

      // Move the file to the target upload folder
      $target = FILE_UPLOADPATH . basename($new_file);
      if (move_uploaded_file($_FILES['new_file']['tmp_name'], $target)) 
      {
        // The new file move was successful, now make sure any old file is deleted
        if (!empty($old_file) && ($old_file != $new_file)) 
        {
          @unlink(FILE_UPLOADPATH . $old_file);
        }
      }
      else 
      {
        // The new file move failed, so delete the temporary file and set the error flag
        @unlink($_FILES['new_file']['tmp_name']);
        echo 'There was a problem with the file upload.' . PHP_EOL;
      }