Converting my main site to nginx has been on my todo list for ages...
When it's switched on, I cannot access the admin section... So there is something wrong in the code I use...
I'm running nginx 1.1.9 (nginx -v) so this might not work for you. Make a backup copy of your configuration file first and see if you can add this above your location ~ \.php$
section.
location / {
try_files $uri $uri/ /index.php;
}
Really, make sure you have that backup of that file first.