Hello,
If you use Comodo certificates over an (web) application that uses OpenSSL and you get the error “unable to get local issuer certificate” that mean that you have to merge the all the certificate chain on one file and submit it on your application as the “CA Certificate”, so OpenSSL will be able to fully resolve the certificate.
Mix this 3 files on one, on this order:
COMODORSADomainValidationSecureServerCA.crt
COMODORSAAddTrustCA.crt
AddTrustExternalCARoot.crt
Then submit the newly created file, along your certificate and your private key to the app that you are setting up, and that should do the trick!
Full Error:
20 X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY: unable to get local issuer certificate
References:
https://www.hmailserver.com/forum/viewtopic.php?t=27316
https://www.openssl.org/docs/apps/verify.html
Regards,
AC.