I gave up on the last attempt and started over with a clean server and installed iRedmail
Installation worked fine.
I go to Lets Debug and get:
No issues were found with pegasus.corp.networkingtechnology.org. If you are having problems with creating an SSL certificate, please visit the Let's Encrypt Community forums and post a question there.
I follow the instructions:
Since the mail server is using a self-signed TLS certificate, both desktop mail client users and webmail client users will see a warning. To fix this, we can obtain and install a free Let’s Encrypt TLS certificate.
First, log into your server again via SSH and run the following commands to install Let’s Encrypt (certbot) client on CentOS 8.
sudo dnf install certbot python3-certbot-nginx -y
iRedMail has already configured TLS settings in the default Nginx virtual host, so here I recommend using the webroot plugin, instead of nginx plugin, to obtain the certificate. Run the following command. Replace with the red text with your own email address and hostname.
For all my trouble and hard work, once again I get the 'Failed to Authenticate' invalid response
Does NOTHING ever work on these 'How-To'?
It uses NGINX and what I know about that could be written on the back of a VERY small postage stamp. I've always used apache, but it doesn't support apache.
Can anyone shed light on what is wrong this time?
Server is Alma 8.6, clean, name pegasus.corp.networkingtechnology.org