Hmm. Honestly, I am hesitant to try to enable EcoRoute. My 3597 recently arrived and unlike with older units, I am not able to do a FULL and COMPLETE backup of my Nuvi. Garmin's drive is 7.5 GB, allocating 7.02 GB max; Used space of 5.19 GB; Free Space of only 1.83 GB.

My Windows settings all show "show hidden files". Garmin has hidden the files so you can't back them up.