Add the following to the vhost: 1location ^~ /.well-known/ { 2log_not_found off; 3}

From Comodo Email after verifying domain ownership, got this hints: 1Root CA Certificate - AAACertificateServices.crt 2Intermediate CA Certificate - USERTrustRSAAAACA.crt 3Intermediate CA Certificate - SectigoRSADomainValidationSecureServerCA.crt 4Your PositiveSSL Multi-Domain Certificate - 378394251.crt Generate the …

1cat AddTrustExternalCARoot.crt COMODORSAAddTrustCA.crt COMODORSADomainValidationSecureServerCA.crt >> cert-chain.pem NOTE: This is the inverse of "Creating an SSL Bundle out of Comodo Positive SSL" which seems valid as well. Not sure if it's valid in any order.

Given this list of files given by Comodo 1Root CA Certificate - AddTrustExternalCARoot.crt 2Intermediate CA Certificate - USERTrustRSAAddTrustCA.crt 3Intermediate CA Certificate - SectigoRSADomainValidationSecureServerCA.crt 4Your PositiveSSL Multi-Domain Certificate - 285695299.crt Do the following: 1cat 285695299.crt …

1www.example.org.crt COMODORSADomainValidationSecureServerCA.crt COMODORSAAddTrustCA.crt AddTrustExternalCARoot.crt >> www.example.org-bundle.crt See details in https://helpdesk.ssls.com/hc/en-us/articles/203427642-How-to-install-a-SSL-certificate-on-a-NGINX-server

Get it via chat to Comodo, one would pop-up from https://support.comodo.com/index.php?/Knowledgebase/Article/View/1145/1/how-do-i-make-my-own-bundle-file-from-crt-files. Make sure you edit your profile where they could send the information.