Error using zeros

I m trying to run an MVPA analysis on a large sample (600 subjects, 2 sessions per subject)

after about 40 hours, i got the following error:

ERROR DESCRIPTION:

Error using zeros
Out of memory. Type "help memory" for your options.
Error in conn_process (line 2790)
c=zeros([Y1.size.Nv(slice),repmat([numel(validsubjects),numel(validconditions)],[1,2])]);
Error in conn_process (line 43)
case 'analyses_gui_vv', disp(['CONN: RUNNING ANALYSIS STEP (voxel-to-voxel analyses)']); conn_process([13],varargin{:});
Error in conn (line 6561)
else conn_process('analyses_gui_vv',CONN_x.vvAnalysis); ispending=false;
Error in conn_menumanager (line 120)
feval(CONN_MM.MENU{n0}.callback{n1}{1},CONN_MM.MENU{n0}.callback{n1}{2:end});
CONN v.17.f
SPM12 + DEM FieldMap MEEGtools
Matlab v.2018b
storage: 696.6Gb available


Any suggestions? I have 32 gb ram