title: Thunderbird Lightning caldav sync doesn't show any data/events
body: <p>when i try to synchronize my caldav server implementation with Thunderbird 45.4.0 and Lightning 4.7.4 (one particular calendar collection) it doesnt show any data or events in the calendar though the last call of the sequence provided the data.</p>
  
  <p>In the Thunderbird error log i can see one error:</p>
  
  <pre><code>Zeitstempel: 07.11.16, 14:21:12
  Fehler: [calCachedCalendar] replay action failed: null,
  uri=http://127.0.0.1:8003/sap/sports/webdav/appsvc/webdav/services/
  server.xsjs/cal/_D043133/, result=2147500037, op=[xpconnect wrapped
  calIOperation]
  Quelldatei:
  file:///Users/d043133/Library/Thunderbird/Profiles/hfbvuk9f.default/
  extensions/%7Be2fda1a4-762b-4020-b5ad-a41df1933103%7D/calendar-
  js/calCachedCalendar.js
  Zeile: 327
  </code></pre>
  
  <p>the call sequence is as follows (detailed content via gist-links):</p>
  
  <ol>
  <li>Propfind <a href="https://gist.github.com/HilmarDemant/6ba124ea473ac7493412421e11c8adf6#file-01_request_propfind" rel="nofollow noreferrer">Request</a> - <a href="https://gist.github.com/HilmarDemant/6ba124ea473ac7493412421e11c8adf6#file-01_response_propfind" rel="nofollow noreferrer">Response</a></li>
  <li>Options <a href="https://gist.github.com/HilmarDemant/6ba124ea473ac7493412421e11c8adf6#file-02_request_options" rel="nofollow noreferrer">Request</a> - <a href="https://gist.github.com/HilmarDemant/6ba124ea473ac7493412421e11c8adf6#file-02_response_options" rel="nofollow noreferrer">Response</a></li>
  <li>Propfind <a href="https://gist.github.com/HilmarDemant/6ba124ea473ac7493412421e11c8adf6#file-03_request_propfind" rel="nofollow noreferrer">Request</a> - <a href="https://gist.github.com/HilmarDemant/6ba124ea473ac7493412421e11c8adf6#file-03_response_propfind" rel="nofollow noreferrer">Response</a></li>
  <li>Report <a href="https://gist.github.com/HilmarDemant/6ba124ea473ac7493412421e11c8adf6#file-04_request_report" rel="nofollow noreferrer">Request</a> - <a href="https://gist.github.com/HilmarDemant/6ba124ea473ac7493412421e11c8adf6#file-04_response_report" rel="nofollow noreferrer">Response</a> - <a href="https://gist.github.com/HilmarDemant/6ba124ea473ac7493412421e11c8adf6#file-04_response_report_raw" rel="nofollow noreferrer">Response Raw</a></li>
  </ol>
  
  <p>The synchronization with other clients like macOS-calendar and ios-calendar works in principle and shows the data. Does anyone has a clue what is going wrong here? </p>