PayPal Instant Payment Notifications Failing

[Shimon Hirschhorn]

Hi,

My website has been pretty stable with no new modules etc.  Over the last 2 weeks I have received warning messages from PayPal stating the the IPN are failing.

I am running VM 2.6.12.2 with Joomla 2.5.24

The message that PayPal send me is :

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

https://www.proflixsales.com/index.php?option=com_virtuemart&view=pluginresponse&task=pluginnotification&tmpl=component&lang=

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.


What is going wrong?
How do I fix it ?

Thanks