Can anyone help with the following...

I have received a PayPal notification email to confirm a payment for a store order.

The order is created in the store and has been allocated an order number and is marked as 'processing' on zen cart admin.

However, the order is showing nothing at all!

I am using v1.3.7.1 and the order is through PayPal IPN.

When I go into Admin Home>Processing and view the ID of the order, in the right hand column it shows everything being correct with the exception that the Products Ordered shows 0.

I have tried installing the PayPal Session Viewer v2.0 but cannot seem to get that installed to try to 'push' the paypal order through but having no luck!

I have had orders previous and after this one that have come through absolutely fine and as they always have...

Any suggestions would be really appreciated as I'm really stuck!