ActiveSync does not sync appointments from iCalendar files

There is a problem with ActiveSync and iCalendar files, at least with Outlook/Exchange:

1. you receive an email with an iCalendar attachment, .vcs or .ics file.
2. you accept the meeting request or double click and add the attachment
3. New appointment shows up in Outlook, but does not sync to all mobile devices

The question for sysadmins here is that is there anything you can do in Exchange or Outlook that would make iCalendar-originated appointments sync like ordinary appointments?

Below is an example of a barebone iCalendar file that synced ok with an iPhone OS4 but failed to sync with Nokia devices:

BEGIN:VCALENDAR
VERSION:1.0
METHOD:PUBLISH
BEGIN:VEVENT
UID:
SUMMARY;ENCODING=QUOTED-PRINTABLE:Header
ORGANIZER:
LOCATION;ENCODING=QUOTED-PRINTABLE:Location
DTSTART:20101001T070000Z
DTEND:20101001T140000Z
DTSTAMP:201010011T072221Z
DESCRIPTION;ENCODING=QUOTED-PRINTABLE:Description
END:VEVENT
END:VCALENDAR

The problem is annoying for any user who receives iCalendar attachments. Unfortunately, I'm not in a position to know which combinations of the handset model, ActiveSync, iCalendar, Outlook and Exchange versions are affected. But I've seen quite a few support requests lately about this. The standard answer is that you can get the appointments sync by editing them manually in Outlook, but this is just not good enough.

See Also:

ActiveSync does not sync appointments from iCalendar files

Outlook events not syncing with ActveSync under mobile 6