How to create a coupon/discount code for a specific group of email address

Hello

I am trying to figure out if Zencart can create a coupon that is specific to a domain name. For example: If I want to offer a coupon to just people who use an email address from only @mil.gov or @au.edu etc.

Is there a way to do that? I've been reading and trying to find out if I can do that, and I can't come up with an answer...

This could be customized to allow ALL coupons to only be valid for various email addresses by editing the file:
/includes/modules/order_totals/ot_coupon.php

by adding the code in RED: around line 357:

          // remove if fails address validation
          if (!$foundvalid) {
            $messageStack->add_session('checkout_payment', TEXT_REMOVE_REDEEM_COUPON_ZONE, 'caution');
            $this->clear_posts();
            if (!$foundvalid) zen_redirect(zen_href_link(FILENAME_CHECKOUT_PAYMENT, '', 'SSL',true, false));
          } else {
          //      if ($_POST['submit_redeem_coupon_x'] && !$_POST['gv_redeem_code']) zen_redirect(zen_href_link(FILENAME_CHECKOUT_PAYMENT, 'credit_class_error_code=' . $this->code . '&credit_class_error=' . urlencode(TEST_NO_REDEEM_CODE), 'SSL', true, false));
            $messageStack->add('checkout', TEXT_VALID_COUPON,'success');
          }
        }

[B]        // bof: check customer email address OHIO-USA.COM or MYLINKSTO.COM
        if ($foundvalid) {
          //echo '$order->customer[email_address]: ' . $order->customer['email_address'] . '<br>';
          if (preg_match('#OHIO-USA.COM#i', $order->customer['email_address']) || preg_match('#MYLINKSTO.COM#i', $order->customer['email_address'])) {
            // valid
          } else {
            // not valid
            define('TEXT_INVALID_COUPON_EMAIL', 'Coupon Valid for Customers with emails from OHIO-USA.COM only!');
            $messageStack->add_session('redemptions', TEXT_INVALID_COUPON_EMAIL ,'caution');
            $this->clear_posts();
            zen_redirect(zen_href_link(FILENAME_CHECKOUT_PAYMENT, '', 'SSL', true, false));
          }
        }
        // eof: check customer email address OHIO-USA.COM or MYLINKSTO.COM
[/B]
      } else {

Just change the email matches to your own ...

If you want this just for a specific coupon, you would need a bit more customization to reference the specific coupon ...