Unable to access clients in CiviCase
That error is almost always related to name vs label mismatches. Check your xml files for the &lt;name&gt; tag and the entries in the database in civicrm_option_value in the "name" column, e.g.

SELECT ov.name, ov.label FROM civicrm_option_value ov INNER JOIN civicrm_option_group og ON og.id = ov.option_group_id WHERE og.name='case_type'