I am having an issue with Magento skipping some - nominal automated emails to both the customer (for order confirmations) and admin (using the New Order Admin extension). I would say a majority of the emails are being sent, but a lot are also being skipped. And its sporadic in this behavior, as it doesn't necessarily happen when high numbers of emails are going out at a time, or even during a slow time. It's all random, and even some days all emails are sent.
I have read everywhere about similar issues and some people point to cron jobs, a problem with the Zend mail function, or a server misconfig. But nothing really helpful. If it makes any difference, the email addresses being used for 'Sales Emails' and admin notifications are hosted by an MS Exchange Server outside of the hosting environment for the Magento site.
Thanks.