Go to RackMail Help
RackMail has put together the best help for setting up your devices that we can find and its specific for your email service and brand of device!
or if you just need settings:
IMAP / SMTP Settings
|Password||your specific email password|
|Incoming mail server name:||secure.emailsrvr.com||Port: 993|
|Outgoing mail server smtp:||secure.emailsrvr.com||Port: 465|