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    Hi,<br>
    <br>
    While upgrading calendarserver from 5.2.2 to 7.0, I am seeing the
    following errors in my log file:<br>
    <br>
    2016-01-19 00:45:19+0530 [-] Log opened.<br>
    2016-01-19 00:45:19+0530 [-]
    [txdav.common.datastore.upgrade.sql.upgrade.UpgradeDatabaseSchemaStep#warn]
    Beginning database schema check.<br>
    2016-01-19 00:45:19+0530 [-]
    [txdav.common.datastore.upgrade.sql.upgrade.UpgradeDatabaseSchemaStep#warn]
    Required database key VERSION: 58.<br>
    2016-01-19 00:45:19+0530 [-]
    [txdav.common.datastore.upgrade.sql.upgrade.UpgradeDatabaseSchemaStep#warn]
    Actual database key VERSION: 28.<br>
    <b>2016-01-19 00:45:19+0530 [-] [calendarserver.tap.caldav#error]
      Data store not available; shutting down</b><br>
    2016-01-19 00:45:19+0530 [-] [memcached-Default] Signal handled:
    Terminated.<br>
    <br>
    Any idea on why this could be happening? What information could I
    provide to debug this?<br>
    <br>
    Thanks,<br>
    Rahul.<br>
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