Email was not sent after a new order

I have my store set up to email me when a new order is placed. For some reason I didn't recieve one over the weekend. It has always worked, it just didn't work that one time. Does anyone have any suggestions on what I can do to make this more reliable?

Exactly what were the circumstances around this "missing" order? What payment method?

I used to experience this with Paypal, upgraded to 1.3.8a and the problem is gone now.

Kim:

Exactly what were the circumstances around this "missing" order? What payment method?

The payment was made with Paypal

yellow1912:

I used to experience this with Paypal, upgraded to 1.3.8a and the problem is gone now.

I'll try that, Thanks

This is now happening to me. The last 3 orders have not been accompanied with the usual email notification.

I've not changed anything to the shop so don't understand how this has happend. Any ideas?

I've been getting this problem on and off again. I just upgrade to 1.3.8a and the problem still shows up intermittently. So I sent my problem to the helpdesk and got this response :

I would like to bring to your attention that we have certain limits on the smarthost server which is responsible for sending mails from web applications. When email is being sent, sender should be specified.
SMTP method for mail sending does provide facilities to specify sender. It is advised to send email using php mail() function from web servers. In order not to share these limits with other customers on your server you should insert the following string before php mail() function in your form: ini_set('sendmail_from', '[email protected]');

.. um how do I implement this in zen cart??

Anyone know how to do this?