Open System Preferences, Internet Accounts, click “Add Other Account” and then on CalDAV account.
Account Type: ManualUser Name: Your full email address (ex. email@example.com)Password: The password you made for your email accountServer Address: The MXroute server you’re on (ex. shadow.mxrouting.net, blizzard.mxrouting.net, etc).
Do the same again but choose “CardDAV account” instead of “CalDAV account” at the Internet Accounts page.