MyBB Community Forums

Can anyone tell me how to make the same format for every post on my forum?

Sometimes it says "Yesterday" etc, but I just want it to have HH/MM, DD/MM/YYYY.

You could try to change in inc/functions.php

function my_date($format, $stamp="", $offset="", $ty=1, $adodb=false)

$ty=1 to $ty=0