Create a .pem file for SSL Certificate Installations

Creating a .pem with the Entire SSL Certificate Trust Chain

1. Log into your DigiCert Management Console and download your Intermediate (DigiCertCA.crt), Root (TrustedRoot.crt), and Primary Certificates (your_domain_name.crt).

2. Open a text editor (such as wordpad) and paste the entire body of each certificate into one text file in the following order:

   1. The Primary Certificate – your_domain_name.crt
   2. The Intermediate Certificate – DigiCertCA.crt
   3. The Root Certificate – TrustedRoot.crt

   Make sure to include the beginning and end tags on each certificate. The result should look like this:

   —–BEGIN CERTIFICATE—– 
   (Your Primary SSL certificate: your_domain_name.crt) 
   —–END CERTIFICATE—– 
   —–BEGIN CERTIFICATE—– 
   (Your Intermediate certificate: DigiCertCA.crt) 
   —–END CERTIFICATE—– 
   —–BEGIN CERTIFICATE—– 
   (Your Root certificate: TrustedRoot.crt) 
   —–END CERTIFICATE—–

   Save the combined file as your_domain_name.pem. The .pem file is now ready to use.

Creating a .pem with the Server and Intermediate Certificates

1. Log into your DigiCert Management Console and download your Intermediate (DigiCertCA.crt) and Primary Certificates (your_domain_name.crt).

2. Open a text editor (such as wordpad) and paste the entire body of each certificate into one text file in the following order:

   1. The Primary Certificate – your_domain_name.crt
   2. The Intermediate Certificate – DigiCertCA.crt

   Make sure to include the beginning and end tags on each certificate. The result should look like this:

   —–BEGIN CERTIFICATE—– 
   (Your Primary SSL certificate: your_domain_name.crt) 
   —–END CERTIFICATE—– 
   —–BEGIN CERTIFICATE—– 
   (Your Intermediate certificate: DigiCertCA.crt) 
   —–END CERTIFICATE—–

   Save the combined file as your_domain_name.pem. The .pem file is now ready to use.

Creating a .pem with the Private Key and Entire Trust Chain

1. Log into your DigiCert Management Console and download your Intermediate (DigiCertCA.crt) and Primary Certificates (your_domain_name.crt).

2. Open a text editor (such as wordpad) and paste the entire body of each certificate into one text file in the following order:

   1. The Private Key – your_domain_name.key
   2. The Primary Certificate – your_domain_name.crt
   3. The Intermediate Certificate – DigiCertCA.crt
   4. The Root Certificate – TrustedRoot.crt

   Make sure to include the beginning and end tags on each certificate. The result should look like this:

   —–BEGIN RSA PRIVATE KEY—– 
   (Your Private Key: your_domain_name.key) 
   —–END RSA PRIVATE KEY—– 
   —–BEGIN CERTIFICATE—– 
   (Your Primary SSL certificate: your_domain_name.crt) 
   —–END CERTIFICATE—– 
   —–BEGIN CERTIFICATE—– 
   (Your Intermediate certificate: DigiCertCA.crt) 
   —–END CERTIFICATE—– 
   —–BEGIN CERTIFICATE—– 
   (Your Root certificate: TrustedRoot.crt) 
   —–END CERTIFICATE—–

   Save the combined file as your_domain_name.pem. The .pem file is now ready to use.

Source: 

https://www.digicert.com/ssl-support/pem-ssl-creation.htm