We have Nagios configured on a Ubuntu VM. We recently changed Windows domains and now need to update this Nagios VM with the right information. We have changed the hostname from "forbes.corporate.local" to "cne-mon01vm.int.cgg.com". Nagios is still working properly, but whenever we get a notification email, it still says it is from "email@example.com". I'd like to change it to say it is from "firstname.lastname@example.org" instead but I can't figure out where to change that.