[cflsystems]

I guess you are talking about all emails send to customers. There are probably few files where you will have to change this. This is the function that sends emails and is in include/func/func.mail.php

function func_send_mail($to, $subject_template, $body_template, $from, $to_admin, $crypted=false)

. YOu will have to find all files using this function and chnage $from to actual email