Postfix configuration : postmap: fatal: bad string length 0 < 1: setgid_group =
just comment out in main.cf the setgid_group = line
#setgid_group =
and rerun
sudo postmap /etc/postfix
just comment out in main.cf the setgid_group = line
#setgid_group =
and rerun
sudo postmap /etc/postfix