Depending on a client's firewall configurations, there may be a need to "allow-list" certain DigiCert IP addresses for the HTTP token domain approval process to go through.
Update allowlists (lists for firewalls that only allow specified IP addresses to perform certain tasks or connect to your system) to allow the below IP addresses. If needed, website configurations should be made to allow the user-agent "DigiCert DCV Bot/1.1".
Service
URL / IP Address
HTTP Domain Validation
216.168.247.9 and 216.168.249.9