25 hours ago
I installed Ubuntu on Windows 7. Also, I installed GROMACS software. There is some problem with one of the files located in /usr/local/gromacs/share/top/ folder. I want to make some changes to and save it, but it always says "Permission denied". I have tried chmod but it says "Operation not permitted".
I really don't know I can change that file. I installed the OS, so I should have the privileges to change the file.
14 hours ago
You have to run chmod command as root. To do this use the command like this:
sudo chmod o+w fileName
With this command you add write permission to "other". Then you have to type your username and password.
"o" is the option for other and you add write permission with "w". Here are other options:
You can read more here.