Error in Running Matlab/SPM "fMRI model estimation"

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Running "fMRI model estimation"
??? Undefined command/function 'spm_list_files'.

Error in ==> spm_config_fmri_est>run_est at 381
[j,unused] = spm_list_files(pwd,files{i});

Error in ==> spm_jobman>run_struct1 at 1379
feval(prog,val);

Error in ==> spm_jobman>run_struct1 at 1387
run_struct1(c.val{i});

Error in ==> spm_jobman>run_struct1 at 1387
run_struct1(c.val{i});

Error in ==> spm_jobman>run_struct at 1346
run_struct1(c);

??? Error while evaluating uicontrol Callback.