WP Super Cache won't cache homepage

I’ve tried to disable every plugin, and it is able to cache every other page and post (including the mobile version of the homepage) without any problem. Only the index page generates these errors:

05:51:01 / supercache dir: /home/resilient/public_html/wp-content/cache/supercache/www.resilientcommunities.com/
05:51:01 / No wp-cache file exists. Must generate a new one.
05:51:01 / In WP Cache Phase 2
05:51:01 / Setting up WordPress actions
05:51:01 / Created output buffer
05:51:01 / Output buffer callback
05:51:01 / No closing html tag. Not caching.
05:51:01 / wp_cache_shutdown_callback: collecting meta data.
05:51:01 / Did not write meta file: wp-cache-89cd61c7a4f54ae61020739b663fea5e.meta ** *1* **

It’s using mod_rewrite and gzip, however I’ve also tried enabling/disabling those different settings, and enabling/disabling ‘Flock’ based on a rackspace knowledgebase article, however still no luck getting the homepage to cache correctly.

I’m not sure what else to try and why it would only be a problem on the homepage.

Thanks

http://wordpress.org/extend/plugins/wp-super-cache/