PayPal requires IPN configuration HSNM Hardware and VM configurations. Sms, Email, Backup, Database

[HSNMSupport]

Today a customer of ours wrote a support ticket:

Hello. When a customer selects a paid product in our hotspot, the process trough PayPal goes OK, but the payment is not checked (acknowledged) by the hsnm and the customer cannot finish the registration process.

This error is due to a missing IPN configuration in your PayPal account.
We encourage you to follow step by step PayPal configuration into Administration Manual to avoid this kind of error.
IPN is mandatory.