This tutorial provides step by step instructions on how to generate a CSR code and install an SSL Certificate on Courier IMAP server. On top of that, the latter sections feature a brief Courier IMP history and useful tips on where to buy the perfect SSL Certificate for your Courier IMAP server.

If you’ve already ordered your SSL Certificate and are looking only for installation guidelines, you can skip the CSR generation part. Use the anchor links below to jump between sections.

Generate a CSR code on Courier IMAP Server
Install an SSL Certificate on Courier IMAP Server
Test your SSL installation
Courier server history
Where to buy the best certificate for Courier IMAP Server?

Generate a CSR code on Courier IMAP Server

The CSR (Certificate Signing Request) code is a block of encoded text with your contact details. You need to create and send it to your CA to pass the SSL validation.

You can generate the CSR code straight at SSL Dragon, with the help of our CSR Generator Tool. Alternatively, you can spend a bit more time and build the shell commands yourself. Please, follow the instructions below:

  1. Connect to your server, and at the prompt run the following command:
    openssl req -new -nodes -keyout your_domain_name.key -out your_domain_name.csr
  2. This command will create your CSR request, and the Private Key, which you’ll need later, during the installation process.
  3. Provide your contact details as shown below:
    • Common Name: enter the FQDN (fully-qualified domain name) of the website you want to secure (e.g.,
    • Organization: type the legal name of your organization. For instance, GPI Holding LLC
    • Organizational Unit: indicate the department requesting the SSL certificate. Usually, it’s IT or Web Administration
    • City/Locality: enter the city where your organization is registered
    • State/Province: specify the state or province where your organization is located
    • Country: enter the two-letter code of your country.
  4. The OpenSSL utility will generate and save the CSR and private key files to the current directory
  5. To open the CSR file, you can use any text editor such as Notepad. You’ll need to copy the entire text including the BEGIN and END tags when ordering your SSL Certificate.

Install an SSL Certificate on Courier IMAP Server

Your CA will send you all the necessary SSL files in a ZIP archive to your email. The ZIP folder will contain your primary, root and intermediate certificates. Follow the steps below to install your certificate:

  1. Download and extract your certificates files to server directory of your choice
  2. Use any text editor such as Notepad, and open your primary certificate file and the private key file (remember, you created the private key along with your CSR code)
  3. Next, you need to merge the contents of your primary certificate and private key into a single file with the .pem extension. Save your new PEM as mycertificate.pem. You can give it any name, just make sure it’s easy to remember. Your PEM file should look like this:
    The Encrypted text of your Primary SSL Certificate
    The Encrypted text of your Private Key

    Note: If your SSL Certificate requires an intermediate certificate file, open your intermediate SSL cert with any text editor and save it as Intermediate_Cert.txt. You can give it any name.

  4. Now you need to import your SSL Certificate. Locate and open your IMPAD-SSL file (the default directory is /usr/lib/courier-imap/etc/)
  5. In the IMPAD-SSL file, add the following directives:
  6. Verify the command that allows SSL3:
  7. Next, locate and open the POP3D-SSL file, which by default resides in /usr/lib/courier-imap/etc/
  8. Add the following command:
  9. Restart your Courier IMAP Server.

Congratulations, you’ve successfully installed an SSL Certificate on Courier IMAP Server.

Test Your SSL Installation

After you install an SSL Certificate on Courier IMAP Server, it’s always wise to scan your new installation for potential errors or vulnerabilities, just to be on the safe side of things. With these powerful SSL tools, you can get instant reports on all aspects of your SSL Certificate and its configuration.

Courier server history

Courier mail server, is a mail transfer agent (MTA) server that offers a wide range of mailing services such as IMAP, SIMPA, POP3, ESMTP, webmail, and mailing list.

Courier was first released in May 2000, by Sam Varshavchik. The current stable release 0.77.0 dates back to June 23, 2017.

Courier is written in C, C++ and, Perl, and runs on Linux, Mac OS X, FreeBSD, and Solaris systems.

Where to buy the best SSL Certificate for Courier IMAP Server?

You’ve already reached the destination! Here, at SSL Dragon, we offer the widest range of SSL products at great prices. All our certificates are compatible with Courier IMAP Server and are suitable for a variety of projects. Browse the list below to find the SSL type you need:

If you don’t know what certificate to choose, or struggling to find the perfect product for your site, our quick, and intuitive SSL Wizard and Advanced Certificate Filter tools will make the search more efficient and enjoyable.

If you find any inaccuracies, or you have details to add to these SSL installation instructions, please feel free to send us your feedback at [email protected]. Your input would be greatly appreciated! Thank you.