Paypal IPN stopped working recently

[Web Host Pro]

Not sure what caused it but new accounts are not getting a call back from Paypal saying the payment is made.

In WHMCS it says: (Please ensure Instant Payment Notification (IPN) is enabled under Selling Preferences within your PayPal account leaving the Notification URL empty. For new PayPal Accounts this is enabled by default.)

But in Paypal when I try to leave it blank it says: You must enter a properly formatted URL into the Notification URL field in order to activate Instant Payment Notification.

And adds our URL: https://webhost.pro

But I think this is just a doc error because it was like this before and worked fine.

Any other ideas why the Call Back would stop working for new accounts? Recurring billing calls back fine.

[WHMCS ChrisD]

Hey @Web Host Pro

Are you getting any errors under Billing > Gateway Logs?

[Web Host Pro]

Hi, it says IPN Handshake Invalid

The details have too much client information to post here.

[Web Host Pro]

I found the language fix, I change it to utf-8. I'll know if that worked in a couple hours.

Interesting. In the paypal log most payments went through fine, just a couple failed for the IPN.

Is there Paypal IPs I can add to my firewall to help the IPN get access?

Oh I found them: 

https://www.paypal.com/us/smarthelp/article/what-are-the-ip-addresses-for-live-paypal-servers-ts1056

ipnpb.paypal.com

64.4.248.8 64.4.249.8 66.211.169.17 173.0.84.40 173.0.84.8 173.0.88.40 173.0.88.8 173.0.92.8 173.0.93.8

Edited April 29, 2018 by Web Host Pro

[WHMCS ChrisD]

Hey @Web Host Pro

Thanks for your reply, setting the Charset Configuration to UTF-8 should solve the issue for you, you shouldn't need to whitelist the IPs