"Copy of Sierra is damaged"

I've tried clean installs on two different USB drives, from both a working hack and a MacBook and fresh installs of OSX from the app store. When I try installing onto my new hack mini, I boot from the USB, and when I try to install from the osx installer, it gives me the "this copy of Sierra is damaged."

Has anyone else had this problem? Google and the search bar haven't helped me out because it seems like everyone else with this issue has it on an actual mac.

Thanks!