Bad Server Response - New Install, file permissions OK

[kmg7513]

With a new install I'm getting a 'Bad server response' - I just went through the wizard without issue, and then got the message (attached).

[yuri]

Check server's error log.

[kmg7513]

I should have clarified - There are no errors generated by the logs, and logging is enabled in nginx.conf:

[COLOR=#00D900][FONT=Monaco][SIZE=10px]access_log /var/log/nginx/access.log;[/SIZE][/FONT][/COLOR]
[COLOR=#00D900][FONT=Monaco][SIZE=10px]error_log /var/log/nginx/error.log;[/SIZE][/FONT][/COLOR]

This is my nginx server block:

server {
listen 443 ssl;
server_name crm.example.com
ssl on;
ssl_certificate /etc/ssl/certs/mysite.pem;
ssl_certificate_key /etc/ssl/private/mysite.key;
ssl_session_timeout 90m;
ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
ssl_ciphers 'EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH';
ssl_prefer_server_ciphers on;
ssl_session_cache shared:SSL:10m;
proxy_set_header X-Forwarded-Proto $scheme;

root /var/www/html;
index index.php index.html index.htm;

location / {
try_files $uri $uri/ /index.php /index.html;
}

location /doc/ {
alias /usr/share/doc/;
autoindex on;
allow 127.0.0.1;
allow ::1;
deny all;
}

location /mirror {
autoindex on;
}

error_page 404 /404.php;

location ~ \.php$ {
fastcgi_split_path_info ^(.+\.php)(/.+)$;
fastcgi_pass unix:/var/run/php5-fpm.sock;
fastcgi_index index.php;
include fastcgi_params;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
}

}

I ran the following commands prior to restarting nginx and php5-fpm to ensure there were no permissions issues:

[COLOR=#00D900][FONT=Monaco][SIZE=10px]find data custom -type d -exec chmod 775 {} + && find data custom -type f -exec chmod 664 {} +;
find . -type d -exec chmod 755 {} + && find . -type f -exec chmod 644 {} +;[/SIZE][/FONT][/COLOR]

As well as:

[COLOR=#00D900][FONT=Monaco][SIZE=10px]chmod -R 755 /var/www/data; chown -R www-data:www-data /var/www/[/SIZE][/FONT][/COLOR]

I'm at a loss...

[EDIT] - I will add that I also followed the guide here https://www.rosehosting.com/blog/how...an-ubuntu-vps/ but supplanted it's nginx server block with my own - after I got the error, I replaced my server block (above) with theirs (below) and it still gave me the same error.

server {
    listen 443 ssl;
    server_name crm.portal.net.co
    ssl on;
    ssl_certificate /etc/ssl/certs/star_portal_net_co.pem;
    ssl_certificate_key /etc/ssl/private/star_portal_net_co.key;
    ssl_session_timeout 90m;
    ssl_protocols       TLSv1 TLSv1.1 TLSv1.2;
    ssl_ciphers 'EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH';
    ssl_prefer_server_ciphers on;
    ssl_session_cache shared:SSL:10m;
    proxy_set_header        X-Forwarded-Proto $scheme;

    root /var/www/html;
    index index.php index.html index.htm;
location /api/v1/ {
if (!-e $request_filename){
rewrite ^/api/v1/(.*)$ /api/v1/index.php last; break;
}
}

location / {
rewrite reset/?$ reset.html break;
}

location ^~ (data|api)/ {
if (-e $request_filename){
return 403;
}
}

location ^~ /data/logs/ {
return 403;
}
location ^~ /data/config.php {
return 403;
}
location ^~ /data/cache/ {
return 403;
}
location ^~ /data/upload/ {
return 403;
}
location ^~ /application/ {
return 403;
}
location ^~ /custom/ {
return 403;
}
location ^~ /vendor/ {
return 403;
}

location ~* \.(?:ico|css|js|gif|jpe?g|png)$ {
expires max;

}

location ~ \.php$ {
try_files $uri =404;
fastcgi_split_path_info ^(.+\.php)(/.+)$;
fastcgi_pass 127.0.0.1:9000;
fastcgi_index index.php;
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
include fastcgi_params;
}
}

[tarasm]

1. Please open Developer tools in your web browser and check the error in a console.
2. Please open the page https://YOUR_DOMAIN/api/v1/index.php. What do you see? It should be a dialog to enter login and password.