You will need 3 files:2_your_domain.crt is from apache.zip you downloaded from StartCom private.key is your private key created when you generate CSR (certificate signing request) 1_root_bundle.crt is from the apache.zip you downloaded from StartCom Save all 3 files in Apache configuration folder /usr/local/apache2/conf/ (or anywhere you prefer). Apache configuration folders can be in different places. Please check your server documentation. In your Apache SSL configuration file ../extra/httpd-ssl.conf (in some distributions httpd.conf) find 3 lines starting: SSLCertificateFile "/usr/local/apache2/conf/server.crt" SSLCertificateKeyFile "/usr/local/apache2/conf/server.key" SSLCertificateChainFile "/usr/local/apache2/conf/server-ca.crt" Change file names (and paths if needed) to your file names. It should look similar to below ones. SSLCertificateFile "/usr/local/apache2/conf/2_your_domain.crt" SSLCertificateKeyFile "/usr/local/apache2/conf/private.key" SSLCertificateChainFile "/usr/local/apache2/conf/1_root_bundle.crt" Restart Apache server.