Last Updated: 3/July/2018
Following domains need to be allowed for secure access (https) in your browser when you use VyNDEX:
Following domain needs to be allowed for secure access (https) in your browser when you sign up for VyNDEX and choose credit card payment.
Salesforce domain needs to be allowed as well when you use VyNDEX. See following Salesforce article how to configure it: