The following is the IP information used by some domain name issuing agencies for HTTP/HTTPS authentication (DCV - Domain Control Authentication). If your domain name cannot issue authentication, please check if the IP is blocked by your website firewall. It is recommended to add the following IP to the whitelist：
SECTIGO is using the following IP addresses to perform DCV (domain control validation):
- 91.199.212.132 - secure.trust-provider.net
- 91.199.212.148 - secure.trust-provider.com
- 91.199.212.133 - mail2.comodoca.com
- 91.199.212.151 - secure.comodo.com
- 91.199.212.176 - www.comodo.com
- 91.199.212.52 - crt.sectigo.com
- 91.212.12.133 - opsmail.dc.sectigo.com
Certum：
194.126.216.17
213.222.200.26
213.222.200.15
213.222.201.155
213.222.198.155
Digicert：
64.78.193.238
216.168.247.9
