Order Confirmation not received

My store is set to send confirmation emails to customers and copy to store owner.
Yesterday I noticed 2 orders in store admin for which I had not received a notification.
order nos 1-103 OK
104 not received
105 received
106 not received.

I only noticed these when checking stock. Fortunately this was only a day later so shipping was not delayed.

I have emailed the customers concerned to ask them to confirm if they received their copy of the 'confirmation email' but have not yet received a reply.

Any one any ideas what went wrong?

Allan

Check the similar threads listed at the bottom of your post

kobra:

Check the similar threads listed at the bottom of your post

I did

I am using PayPal Express
When I receive order confirmation - I do receive paypal notification
Order is in admin
I never receive paypal notification without order confirmation

so all 4 'similar threads' references are not relevent

Get the email archive plugin
This will tell you if ZenCart has created the email
If it has, then it is passed to your email server and out of ZenCart's hands

Yes - I suspect it is ISP related as it is 'intermittent' - i will give the plug in a try

Thanks

I am feeling 'stoopid' at the moment
I downloaded the email archive - latest version - it says compatib;e with 1.3.9h
copied files into admin as directed
enabled email archiving
but I dont see the 'E-Mail Archive Manger' under tools - grr

Advice appreciated

rmoved 1.7 and installed 1.6 - thats OK

but I dont see the 'E-Mail Archive Manger' under tools - grr
You might need to use phpmyadmin and browse the table created

kobra:

You might need to use phpmyadmin and browse the table created

Thanks fo rthe input.

I have Email Archive add-in working with the 1.6version of the tool.