@myman said in Unbound: fatal error: Could not read config file: /unbound.conf:

unbound-checkconf returns unbound-checkconf: no errors in /usr/local/etc/unbound/unbound.conf

Runing " unbound-checkconf" will check the default /usr/local/etc/unbound/unbound.conf, a file that exists, but it is just a demo file.
The real "unbound.conf", the one unbound for pfSense is using, is here/var/unbound/

Your unbound is restating every couple of minutes.
If these restarts happen to often, then the start code can overlap with another startup. Then one of then can fail and you see the error shown.

Disabling "DHCP registration" is one of the first things to try.