This will entirely depend on your operating system, and mail server. Some general guidlines are listed here:
- Your cert will usually need to be in ‘pem’ fashion. That is, both key and cert in one file.
- Your mail server must support SSL/TLS.
For example, if you have a CPanel server, you can use your cert by editing the following files to contain your cert/key:
After your certificate has been installed, you will need to restart CPanel, which should automatically restart Exim.