[lammps-users] problem with dump xyz

hello.
i am using the command:
dump 1 all xyz 1000 diamante.xyz

and the format:
dump 1 all atoms 1000 diamante.xyz
dump_modify 1 header xyz

for obtain a serious of xyz images with lammps, but this command line don't run, someone can tell my what are making bad?.
thank you.