Hi, It sounds like the installation has not correctly set up your shell. See <http://fsl.fmrib.ox.ac.uk/fsl/fslwiki/FslInstallation/ShellSetup> http://fsl.fmrib.ox.ac.uk/fsl/fslwiki/FslInstallation/ShellSetup for instructions on doing this, unless you are using neurodebian, in which case do "man fsl" and follow the instructions there. All the best, Mark From: FSL - FMRIB's Software Library <[log in to unmask]<mailto:[log in to unmask]>> on behalf of Dorsa Haji Ghaffari <[log in to unmask]<mailto:[log in to unmask]>> Reply-To: FSL - FMRIB's Software Library <[log in to unmask]<mailto:[log in to unmask]>> Date: Friday, 8 July 2016 at 18:47 To: "[log in to unmask]<mailto:[log in to unmask]>" <[log in to unmask]<mailto:[log in to unmask]>> Subject: [FSL] question about run_first_all Hi, I have installed the VMplayer and the fsl package but when I try to use the run_first_all command on my images I get the error: "command not found". I appreciate any suggestions. Thank you Dorsa