[gmx-users] mdp wrong

[Dallas B. Warren]

 > follow the last problem ,i checked my gro,itp and modifid,but this
time 
> ,"invalid command line argument",what's that mean? is still my
mdp'wrong? 
> but this mdp that i test well in other gro ,and itp in ffgrom96,and
this time 
> ,my forcefield is ffoplsaa,is there any different in the mdp? 

It means exactly what it says, there is a command line argument that is
incorrect.

What is the exact command that you executed to run the script?  There is
likely a space in the command line text, incorrect letter or something
like that.