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I tried to change an event in my calender (I'm the owner, it's published to several employees).

when I finished the new event I receive the following message

After clicking "zurück zum Server" nothing happen. The invitations are not sent and the event is not updated in the iCloud.

This is important for us because the whole employee schedule is managed by iCal (sometimes unfortunately, it is not that professionaly made for business)

Thanks for any help