I am currently working on synthesis of organic compounds and their metal complexes. For the theoretical calculation of ligands and metal complexes, I use Gaussian 16 linux version. I am facing the problem with chk file. If I tick the chk file option in link section, It shows the Ntrex error. However if I don't save chk file it work fine. But for drawing the surfaces of humo and lumo, I need chk file of optimised structure. So, I am writing this message to you with the hope that you will help me out to get rid off this problem. Hope for the quick and positive response.