Magento – There is no cron_email_queue & cron_email_queue_recipients tables in the database. Not sending order confirmation emails, in magento 2

Have you checked your Magento logs yet? We recently had a client who reported the same symptom on their 1.9.1 installation. When we checked the Magento logs, we discovered that their system was making calls to a PHP module called mb_string() which were failing.

Fatal error: Call to undefined function mb_convert_encoding() in /public_html/lib/Pelago/Emogrifier.php on line 556

That mb_string() function is used in Magento 1.9.1 to strip out CSS styles from your email templates and inline them into your outbound email HTML code for supporting Mail Clients that won’t render CSS 3 styles : http://www.myintervals.com/blog/2014/12/02/magento-and-the-intervals-emogrifier-class/

Their web host did not have this PHP module installed / enabled, so the function calls were throwing errors before the logic that sends the actual message can be executed, causing emails to not be sent.

If your logs show a similar error, you may need to contact your web hosting provider to see if they can enable support for mb_string()

If they don't support it, you'll need to find another host who offers support for it if you want to continue running 1.9.1

If this error isn't being thrown in your logs, you may find one of the answers submitted in this discussion may apply : New order email confirmation not being sent

Try a workarround:

in CMS > SALES EMAILS Set Order > Sent Emails via seperate Mail (BCC is Buggy)

Magento know this bug and will fix in 2.0.