I'm trying to send same email to several users at once. They should not see each other's email addresses, so I add them as
Bcc in the header.
However, the problem is that Drupal seems to require the
$to parameter passed to
drupal_mail() function. I tried passing both
NULL and an empty string but without success. System would return the
Unable to send e-mail. message.
I don't want to use some random email address instead and I want to avoid new modules.
How can I send an email just with BCC recipients?