mdfil: Error unknown flag: 
                                                                                                                                                                                                                                                               

     usage: sander  [-O|A] -i mdin -o mdout -p prmtop -c inpcrd -r restrt
                   [-ref refc -x mdcrd -v mdvel -e mden -idip inpdip -rdip rstdip -mdip mddip -ng numgroup -remlog rem.log -remtype rem.type -rem [0|1|2] -rremd [0|1|2|3] -saveene saveene -clusterinfo cluster.info -reservoir reserv/frame -hybridtraj hybrid.strip.crd-ng numgroup -remlog remlog -rem [0|1|2] -inf mdinfo -radii radii -y inptraj -amd amd.log]
Consult the manual for additional options.