I would like to attach an e-mail to ical 6.0 appointment...
You can drag the email from Mail's list of emails into the event's url field (when the event is in edit mode) to make a link to the email from iCal.
I'm glad it helped.
I just tried to drag and drop an email to an iCal event, and it will not work. I can't understand why. Is it possibly because the calendar is a Google CalDAV? Thought I might have read that somewhere.
I think in general it does not work in CalDAV calendars, as the file remains local and would not be accessible to other viewers of the CalDAV calendar.
From memory Apple have this working for iCloud calendars though.
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