Start situation: an appointment has been made in Outlook by a secretary for her manager and others (including me). Accepted by me. Shows up in Thunderbird / Lightning, so far so good.
Problem: when the appointment is changed later by the secretary (another day for example), the changed appointment shows up in Outlook but not in Lightning and the original appointment has disappeared.
Ubuntu 13.04 / Davmail 4.3.3-2146 / TB 17.06 / Lightning 1.9.1 / Exchange 2007 126.96.36.199. EWS, Wedav or Auto doesn't make any difference.
Problem also occurred is older versions of Ubuntu / TB / L and Davmail.