I have a model in Visual Modflow Classic and trying to run WinPEST using concentration values in the objective function.
When I used head values as the objective function to estimate parameters with PEST, it ran fine. But when I use only concentration values, I keep getting an error:
"Cannot open model output file "projectname.001.COB."
I am running everything as an administrator and cannot even find a .COB file on my computer.
I've uninstalled and reinstalled the program, tried different versions of the models, and even changed the number of concentration observations to reduce complexity. I can't get PEST to run.
Anyone ever see this error or have recommendations on what to do?
Thanks so much!