Ok. Anyway, I tested this import command and it's working nicely on 7.1.1. There is no invitation email sent, the appointment simply shows up in the calendar:
Originally Posted by bowen
..to be executed as the zimbra user.
zmmailbox -z -m firstname.lastname@example.org pru /Calendar cal.ics
If you want invitations you could to start from an existing event (i.e. with a UID field in the ics file) and then send mails either from the GUI or with a script..
To know how the ics file should look like you can create an event, then rightclick on it and have a look at the original fields assuming this is possible in version 6.