How to install intermediate certificate on an Apache server with OpenSSL 1. Copy the chain certificate, from the certificate pick up page, and paste it into a text editor. The certificate should have this form: -----BEGIN CERTIFICATE----- MIIETTCCAzWgAwIBAgIESyDyzjANBgkqhkiG9w0BAQUFADCBsTELMAkGA1UE BhMCVVMxFjAUBgNVBAoTDUVudHJ1c3QsIEluYy4xOTA3BgNVBAsTMHd3dy5l . . . Fr4NBGoyp0TvTLv9/mIyijCD+AVs+U7vY20nTPeGUsKAFI+u0Hy7MduF8Pt2 8lwRdW7dJnvVl+igWtI/0yXfZahFsPDCl1naLrhazeritKllugMtCXqWlRmA uyCntu+draHBu/JihC8135lB8XvhYaZlbg== -----END CERTIFICATE-----
Make sure to copy the -----BEGIN CERTIFICATE----- and the -----END CERTIFICATE----- and that there is no trailing spaces or carriage returns.

2. Save the text file using a .crt file extension . 3. Rename the file to a .crt file extension. 4. Open your server’s HTTPD.CONF or SSL.CONF file and locate your virtual host entry for the domain to be secured by this certificate. ​If you are not sure where you HTTPD.CONF file is located run the following command:

openssl version -a

You will see at end of command output "OPENSSLDIR:" this is the path that is configured where OpenSSL will look for configuration files

5. Add the following line under the virtual host entry of your site/domain in the HTTPD.CONF or SSL.CONF file: SSLCertificateChainFile <path to certificate>/<chain certificate>.crt Sample of the HTTPD.CONF or SSL.CONF:
If you have any questions or concerns please contact the Entrust Certificate Services Support department for further assistance.

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