Page Caching

I’m using Hostgator, installed the plugin enabled page caching but it still shows disabled????

Engine: disk: enhanced
Cache key: http://www.sitename.com/_index.html
Caching: disabled
Reject reason: DONOTCACHEPAGE constant is defined

Seem like Hostgator have blocked something or the plugin doesn’t detect public users.

The page is a static home page. Any ideas??

http://wordpress.org/plugins/w3-total-cache/