Originally Posted by MultipleParadox
Drake: Never saw that checkbox :P (it's not displayed when replying to a PM though). I'm pretty sure they were showing in my sent box before
Yeah, it doesn't show up in Quick Reply, you need to click on Go Advanced
There's an option to set the default in your User CP:
User CP -> Settings & Options / Edit Options, or follow this link:
in the Messaging & Notification
group you'll see Save a copy of sent messages in my Sent Items folder by default
at the bottom.