Leverage browser caching of static assets. 1 error.

Getting this error only on the root part of our domain. (so have a score of 95% for this category)

FAILED - (No max-age or expires) - http://www.mydomain.com/


I am using NGINX. Everything else has a green checkmark. (css file and images) Its just the root domain.

A server admin set it up in the NGINX config file but all i can see related to NGINX is the following:

"proxy_cache_valid 200 2m;

limit_conn_zone $binary_remote_addr zone=lz:10m;
limit_conn lz 60;

limit_req_zone $binary_remote_addr zone=eigth:4m rate=7r/m;
limit_req_zone $binary_remote_addr zone=fourth:4m rate=15r/m;
limit_req_zone $binary_remote_addr zone=half:4m rate=30r/m;
limit_req_zone $binary_remote_addr zone=one:4m rate=1r/s;
limit_req_zone $binary_remote_addr zone=two:4m rate=2r/s;
limit_req_zone $binary_remote_addr zone=three:4m rate=3r/s;
limit_req_zone $binary_remote_addr zone=four:4m rate=4r/s;
limit_req_zone $binary_remote_addr zone=five:4m rate=5r/s;
limit_req_zone $binary_remote_addr zone=six:4m rate=6r/s;
limit_req_zone $binary_remote_addr zone=seven:4m rate=7r/s;
limit_req_zone $binary_remote_addr zone=eight:4m rate=8r/s;
limit_req_zone $binary_remote_addr zone=nine:4m rate=9r/s;
limit_req_zone $binary_remote_addr zone=ten:4m rate=10r/s;
limit_req_zone $binary_remote_addr zone=twelve:4m rate=12r/s;
limit_req_zone $binary_remote_addr zone=fifteen:4m rate=15r/s;"


No idea what that is but its working for everything but the root of our domain.

Anyone can get us up to 100%?