Dear All, I am trying to run phenix.refine but I keep getting the message: Sorry: Fatal problems interpreting PDB file: Number of atoms with unknown nonbonded energy type symbols: 308 Please edit the PDB file to resolve the problems and/or supply a CIF file with matching restraint definitions. Note that elbow.builder is available to create restraint definitions. I have run my ligands through elbow and used the output .cif but I still get the same message. I can find no info on this problem in the manual or the BB, can anyone help? Thanks in advance, yours, Matt. Matthew Bowler MRC Dunn Human Nutrition Unit Wellcome Trust / MRC Building Hills Road Cambridge CB2 2XY Tel: 0044 (0) 1223 252826 Fax: 0044 (0) 1223 252825