HTTP/1.1 412 Precondition Failed
Date: Dow, 01 Jan 2000 00:00:00 GMT
DAV: 1, 2, 3, access-control, calendar-access, calendar-schedule
DAV: extended-mkcol, calendar-proxy, bind, addressbook, calendar-auto-schedule
Content-Length: 178
Content-Type: text/xml; charset="utf-8"

<?xml version="1.0" encoding="utf-8" ?>
<error xmlns="DAV:">
  <urn:ietf:params:xml:ns:carddav:supported-address-data/>Incorrect content type for addressbook: text/plain
</error>