i am trying to install a php program called zen cart. ive uploaded all the files but 3 pages into the installation and i encounter a internal server error.
If it is php script then it should be 644 and if there is any log files that needs to be written by scripts then it's permissions should be set to 755. Did you see your site's error log?What it is saying?
Enable viewing of hidden file in file manager and Change permission of /home/***/public_html/
zc_install/.htaccess to 644 and if doesn't exists then create new.
You can delete error messages you post above for security, because it is revealing your cPanel user name.
It is happening because according to error_log .htaccess is not readable.You have corrected its permission?If yes then try renaming it and then open ../../install.php if it works or not.