Dear SPMers, I just click on Full Factorial desing and get the following error message (I set the debug to stop to catch the error type): case {'repeat','choice'}, if isfield(c,'values') for i=1:numel(c.values) c.values{i} = insert_defs(c.values{i}); end; end; end; if isfield(c,'val') for i=1:numel(c.val) c.val{i} = insert_defs(c.val{i}); end; end; %---------------------------------------- I am using Windows XP Professional and Matlab 7 if this could be the problem (which I doubt). Thanks a lot, Shary