Paypal IPN Notifications and settings

Hi People

Just recently, one of my clients received an email from paypal saying that…

Please check your server that handles PayPal Instant Payment Notifications (IPN). IPNs sent to the following URL(s) are failing:

https://www.yourwebsite.com/callback/

If you do not recognize this URL, you may be using a service provider that is using IPN on your behalf. Please contact your service provider with the above information. If this problem continues, IPNs may be disabled for your account.

Thank you for your prompt attention to this issue.

I’m not really sure what to do as this is the first time i have encountered an issue like this, what do i need to change in the paypal account to rectify this?

Also, when i make a payment for a product, the customer receives about 10 emails saying thank you for your purchase, etc, etc so i am assuming it has something to do with the IPN issue??

Can anyone shed some light on this?

Darren