appologies, CA is valid. Did you include lipid.itp before including dmpc.itp?
I can't see what the problem is. Send your full commands and your top file. _______________________________________________ gmx-users mailing list [email protected] http://www.gromacs.org/mailman/listinfo/gmx-users Please don't post (un)subscribe requests to the list. Use the www interface or send it to [EMAIL PROTECTED] Can't post? Read http://www.gromacs.org/mailing_lists/users.php

