Is the site's ssl certificate suitable for the mail server?

Question

linux

Good day.
I set up a mail server with support for TLS encryption of traffic
But there is a problem, the mail client gives a warning when it starts up It

is clear that the problem is that I generated the certificate
myself I have the following question: I already have a certificate from godaddy for this domain, it will suit the mail server ? Or are the types of certificates different?
Sorry for the noob question, but I only have this night to study this issue, tomorrow night at the most
Thanks.

Answer 1

The certificate will do. I have a postfix mailer. The usual certificate and key for Apache are fine.
What is your domain certificate? If *.mymedia.ge then it will do. If www.mymedia.ge - then no.
You can get free certificates from startssl or woosign if needed.

Answer 2

Will do. An SSL certificate is an SSL certificate. You can use it in any software that supports SSL/TLS. The question can only be in the form of packaging of its components for a particular software.
The name of the node with which the connection is made must match the name written in the certificate.

Answer 3

What will fit is written in the comments above. I will only note that so that mail clients do not swear at the certificate - correctly prescribe the chain. In one file, in addition to your .crt, there must also be a godaddy root certificate, etc. intermediate certificate, just write them to a file one by one and specify the path to this file in the smtp server settings. root.crt can be found on the godaddy website.