Error in load pdb file for HADDOCK

i wand to do HADDOCK but when i want to load my proteins in first step this error to be appear:

“Error in PDB file. Your PDB contains multiple residues with number 126 in chain A or duplicated atom names”

what can i do?

Hi, this means that you have more residues with number 126 in chain A. If you have a pdb file with more conformations per amino acid, each with different occupancies, you can use this pdb_tool script: or manually delete the residue or atom duplicates. script by default picks the atom with the highest occupancy values.