DRCSCS "<username>@cs.uwaterloo.ca" email supports School approved <address>'s that are not provided by IST.
Host mail.cs.uwaterloo.ca provides these services and is supported on a "business hours best effort" basis .
To read email please use IMAP Settings
To send email please use SMTP Settings
To use the UW Address book LDAP service (provided you are on or VPN'd to campus).