How can I get Frontier Design AlphaTrack driver to install in El Capitan?
How can I get Frontier Design AlphaTrack driver to install in El Capitan?
Mac Pro, OS X El Capitan (10.11.4), Using multiple partitions
https://www.frontierdesign.com/Support/Contact
try using the above link.
https://www.frontierdesign.com/Support/Downloads
or this link for drivers
...or posting more details about what you have already tried, what software you are using it with, what is happening now...