I had the same issue and resolved it by going into phpMyAdmin within Cpanel.
From here, I went to the fo_dimensions and inserted a new row and gave it the name 'test'. You can do the same or you can copy & paste my code into your SQL.
INSERT INTO fo_dimensions` (`id`, `code`, `name`, `is_root`, `is_manageable`, `allows_multiple_selection`, `defines_permissions`, `is_system`, `is_default`, `default_order`, `options`) VALUES (NULL, '', 'Test', '0', '0', '0', '0', '0', '1', '0', '');
This works on 2.1 & 2.2beta