I would like the pnp4nagios app to be accessed as: http://server/pnp4nagios/. With this URL it gives a 403 Forbidden error. It works when I give: http://server/pnp4nagios/index.php.
What might be wrong?

Here is the pnp4nagios location config:

location ~ /pnp4nagios {
alias $pnp4nagiosbase/share;
auth_basic "Nagios Restricted"; ## Message shown in login window
auth_basic_user_file $nagiosbase/etc/htpasswd.users ; ## See /etc/nginx/htpassword
index index.php;
try_files $uri $uri/ @handler ; ## If missing pass the URI to Magento's front handler

location ~ /([^\/]*\.php)$ {
alias $pnp4nagiosbase/share/$1;
#include /etc/nginx/fastcgi.conf;
fastcgi_pass $fcgipass;
fastcgi_param SCRIPT_FILENAME $fastcgi_script_name;
include fastcgi_params; ## See /etc/nginx/fastcgi_params
}

location ~ \.php$ {
#include /etc/nginx/fastcgi.conf;
include fastcgi_params; ## See /etc/nginx/fastcgi_params
fastcgi_pass $fcgipass;
}

}

Thanks,
Yash