Email to registered subscriber with computer generated password ??

We have elected to pre-register our subscribers – so User Registration is currently not allowed. However, when I assign the user id and register them from the back end of the directory as an Administrator, I cannot find where the Email to notify the new subscriber that his/her User ID and computer generated password has been created so that he/she may log in and complete their profile.

So no one is getting notices.

Help please
EveLynn