This could be due to just a long period of disuse, thus the seals have dried up, or it could be a more serious problem.
Sometimes my car gets driven 30-40 miles in the whole year.
If I run the A/C every few months (5 miles or so), is that enough not to have a prolonged "disuse" so that the system stays operational and seals don't dry up?
2007 Chili Red Elise
2009 Chrome Orange Exige S260