I've tried them all; peppermint oil, moth balls, steel wool sprayed with Lysol and more. Nothing has really worked for the long haul.
Here's a tip: We camp 2-3 weekends a month through the summer. I hate unloading all the food each time to keep it away from the mice. I bought a food storage bag called a Grubpack. I bought it on-line. It's a bag made of flexible metal mesh. I store pancake mix, sugar, potatoes, raisins, crackers and all my other un-canned dry foods in the Grubpack. Mice can't chew through it and the food stays safe. ... View related article.