Open up thunderbird and head to the right hand menu area which contains your email addresses, and right click on top of your Computerisms hosted Email Account
In the context menu that appears, select Settings
Head down to the bottom of the side menu, to the option labeled Outgoing Server (SMTP)
Find the item in the list named yourdomain.tld Mail - mail.yourdomain.tld and select it
Check the details of the selected server below:
If it says Port: 465 and Connection Security: SSL/TLS then congrats! You're already set up! You can skip the rest of this guide
If you instead see Port: 587 and Connection Security: STARTTLS we'll need to make some changes, following the steps below
Click on Edit... on the right hand side
Change the Port under the Settings header to 465 and the Connection Security down under Security and Authentication to SSL/TLS and click on OK.
You're done! Feel free to close the account settings tab that had been opened in the main Thunderbird window
Outlook
Go to the Windows Start Menu and search for Control Panel. Go ahead and open it
In the Control Panel, head to the search bar, above, and search for Mail. You should see it come up in the search results. Click on it
Once that opens up, you should see three options. You want to select E-mail Accounts...
In the windows that opens up there, select your Computerisms hosted email account and select Change... in the area above
In this window, select More Settings...
Switch to the Advanced tab
Change the Port in the Outgoing server (SMTP) to 465 and SSL underneath that
You're done! Outlook will likely run a quick check of the new settings when you go to exit from the various windows and you should be good to go!
