warning Bond/angle/dihedral extent > half of periodic box length

first off, please always reply to the mailing list, not individual people.

thanks Axel

but I can not understand how to solve my problem.
when I change dimensions of box or delete dihedrals in data file ,I do not
get this error. is it correct?

it is a warning, not an error (otherwise you have an outdated version
of LAMMPS and shout update). and *you* *should* know whether this is a
warning that you can ignore or not. if not, then you have to correct
your data file. i most certainly cannot, since i cannot know what is
your input.

sorry, but this is definitely a case you you have to know yourself
what is right or wrong. there is no single answer.