Dear All: I am doing co registration two scans by using SPM5. I got error messages as below. Does anybody know if this means my SPM5 download has problem? Thank you very much for your help. Ying -------------------------- Running "Coreg: Estimate & Reslice" Error running job: Error using ==> offset>asgn at 33 "offset" must be a positive integer. In file "C:\Program Files\spm\spm5\@file_array\private\offset.m" (v253), function "asgn" at line 33. In file "C:\Program Files\spm\spm5\@file_array\private\offset.m" (v253), function "offset" at line 17. In file "C:\Program Files\spm\spm5\@file_array\file_array.m" (v315), function "file_array" at line 34. In file "C:\Program Files\spm\spm5\@nifti\nifti.m" (v253), function "nifti" at line 70. In file "C:\Program Files\spm\spm5\spm_vol_nifti.m" (v112), function "spm_vol_nifti" at line 16. In file "C:\Program Files\spm\spm5\spm_vol.m" (v982), function "subfunc" at line 141. In file "C:\Program Files\spm\spm5\spm_vol.m" (v982), function "subfunc1" at line 87. In file "C:\Program Files\spm\spm5\spm_vol.m" (v982), function "subfunc2" at line 73. In file "C:\Program Files\spm\spm5\spm_vol.m" (v982), function "spm_vol" at line 57. In file "C:\Program Files\spm\spm5\spm_coreg.m" (v1007), function "spm_coreg" at line 109. In file "C:\Program Files\spm\spm5\spm_config_coreg.m" (v1032), function "estimate_reslice" at line 322. -------------------------- Done.