Hi, I tried to get the Coulombic surface coloring for one of the protein that I modified by removing certain residue at the C-termini and then mutated some residues to the non-natural amino acid 5,5,5-trifluoroleucine using Swisssidechin option. I am getting this error which I am not able to understand. Disabled GPU programs because a graphics driver bug was encountered while compiling a vertex shader. #0, chain A: COMP #0, chain B: COMP #0, chain C: COMP #0, chain D: COMP #0, chain E: COMP C:\Program Files\Chimera 1.8.1\bin\mscalc.exe 1.400000 2.000000 1 MSMSLIB 1.3 started on Local PC Copyright M.F. Sanner (March 2000) Compilation flags Surface CC TFLE.pdb, category main, probe radius 1.4, vertex density 2 22 connected surface components Total solvent excluded surface area = 10393.6 component areas = 8599.46, 624.842, 225.9, 216.153, 81.7059, 54.8894, 54.839, 48.0624, 45.9525, 43.9588, 41.5667, 39.1204, 38.7549, 37.0513, 35.5418, 33.6712, 32.9167, 28.9293, 27.8262, 27.7523, 27.7319, 26.9429 Total solvent accessible surface area = 10372 component areas = 9971.67, 202.012, 92.2225, 70.7414, 13.8165, 4.12717, 3.62753, 3.24856, 2.597, 1.1866, 1.72654, 1.33137, 1.08737, 0.962375, 0.64812, 0.231422, 0.40193, 0.120068, 0.0570046, 0.0515394, 0.0674059, 0.0311705 No SEQRES records for combination (#-2147483648.-2147483648) chain A; guessing terminii instead No SEQRES records for combination (#-2147483648.-2147483648) chain B; guessing terminii instead No SEQRES records for combination (#-2147483648.-2147483648) chain C; guessing terminii instead No SEQRES records for combination (#-2147483648.-2147483648) chain D; guessing terminii instead No SEQRES records for combination (#-2147483648.-2147483648) chain E; guessing terminii instead Chain-initial residues that are actual N terminii: #-2147483648.-2147483648 MET 27.A, #-2147483648.-2147483648 MET 27.B, #-2147483648.-2147483648 MET 27.C, #-2147483648.-2147483648 MET 27.D, #-2147483648.-2147483648 MET 27.E Chain-initial residues that are not actual N terminii: Chain-final residues that are actual C terminii: #-2147483648.-2147483648 TFLE 67.A, #-2147483648.-2147483648 TFLE 67.B, #-2147483648.-2147483648 TFLE 67.C, #-2147483648.-2147483648 TFLE 67.D, #-2147483648.-2147483648 TFLE 67.E Chain-final residues that are not actual C terminii: 424 hydrogen bonds Hydrogens added Charge model: AMBER ff12SB Assigning partial charges to residue TFLE+TFLE (net charge +0) with am1-bcc method Running ANTECHAMBER command: C:/Program Files/Chimera 1.8.1/bin/amber12/bin\antechamber -ek qm_theory='AM1', -i c:\users\haresh~1.pol\appdata\local\temp\tmpipssqi\ante.in.mol2 -fi mol2 -o c:\users\haresh~1.pol\appdata\local\temp\tmpipssqi\ante.out.mol2 -fo mol2 -c bcc -nc 0 -j 5 -s 2 (TFLE+TFLE) Cannot automatically determine charges for residue TFLE+TFLE; Run AddCharge tool manually to add charges and then rerun ESP Can someone please tell me a step by step procedure to make this work. Thanks & Regards, Haresh