hallo FSL-group! when I run DTIFIT from the Fdt window, I've got this message: " Errors:terminate called after throwing an instance of 'NEWMAT::IndexException' " Could somebody help me resolving this problem? Thanks a lot AC p.s.If it helps, I'm running FSL 4.0 on Ubuntu 7.04 and I'm analyzing a DTI phantom dataset.. thanks again.