Important to note:
To allow the SSL security to work when setting up your email a valid SSL Certificate will need to be set up on the domain name and email service. Contact support if you need assistance with this.
The mail server settings are the domain name only without any prefix.
IMAP Server: example.com (Use your domain name only)
SMTP Server: example.com (Use your domain name only)
Security type: SSL
Username: Your full email address
Password: As set up when creating the email account
If you have any issues setting up your email on your Plesk Hosting please contact support.