The MyBB Humanization Project

[brad-t]

You need to set those fields as hidden and checked.

<input type="hidden" name="emailpmnotify" id="emailpmnotify" value="1" {$emailpmnotifycheck} />
<input type="hidden" name="receivepms" id="receivepms" value="1" {$receivepmscheck} />
<input type="hidden" name="pmnotice" id="pmnotice" value="1" {$pmnoticecheck} />
<input type="hidden" name="allownotices" id="allownotices" value="1" {$allownoticescheck} />