I am trying to "Dynamics (Equilibrate)" a membrane protein model (a protein, ions, lipids, and water). I loaded a single pdb with the above components,displayed the structure and attempted to do "Apply Forcefield". It does not matter which force field type I select, I get the same error message "There was an error ...: Nonstandard chemical bonds are found on atoms such as DOPC2:215, which cannot be typed...". DOPC refers to a lipid type. Any suggestion at all? Thank you!