Tascam US-428 Not Recognized by Cubase 4

The Tascam US-428 Digital Workstation controller isn’t recognized as the ASIO driver by Cubase. I’ve tried the usual fixes: Downloaded a new driver, plugged and unplugged the USB cable, attended to the sequence of power-on issue (who goes first). Still nothing. I’m hoping someone has a simple fix for me. I hope the US-428 isn’t so old that no one is familiar with it. The manual says plug it in. It worked on my older computer, but not on this new one MacPro 10.8.5.