Dear All
Recently I noticed when account is created (D7), Drupal send a welcome mail to user (mode is no_approval_required),
the format of the mail is something like this ..
user,
Thank you for registering at <site>. You may now log in by clicking this link or
copying and pasting it to your browser. Please set your password accordingly.
<link>
username: user
-- <site> team
This was working fine till recently. Then I have written a custom module to send group mails. It is very simple, reads all mail ids from a table and send mail one by one just making use of PHP's inbuilt mail function.