I'm a first time admin using SMF. My board is set up to require admin approval after resgistration. The board is sending a mail to confirm that registration has been requested, but it is not sending the second mail once approval has been given. I've read the posting at http://www.simplemachines.org/community/index.php?topic=12628.0 about reverse DNS but that doesn't seem to answer this problem, since one mail is getting through, why not the other? All help appreciated.
I had the same problem.
My solution to this is that you DONT activate a new member from the members profile.
Instead go to Administration panel -> registration management -> chekc the box next to the member and select "Aprove and send email" in the drop down box. ;)
I hope this works as good for you as it does for me !
Got it, thanks, it worked for me. And I also managed to change the text of the message by editting login.english.php (may be a useful tip to others).