Dear Erica, Start by just re-running the concat_bvars, and if that doesn't work then try rerunning all the segmentations. All the best, Mark On 2 Dec 2011, at 15:23, Erica Grodin wrote: > Hi Mark, > > I updated my fsl to 4.1.9 and am still getting the NEWMAT::SingularException error. Do I need to rerun the earlier steps with the updated version to avoid this problem? > > Thanks, > Erica >