Reading password protected excel file

this.excelWorkbook = this.excelApp.Workbooks.Open(                 fileName, vk_update_links, vk_read_only,                  vk_format, vk_password,                 vk_write_res_password,                  vk_ignore_read_only_recommend, vk_origin,                 vk_delimiter, vk_editable, vk_notify,                  vk_converter, vk_add_to_mru,                 vk_local, vk_corrupt_load);