[Plugin: Extended Live Archive] not seeing categories

Hi, my Extended Live Archive configuration page does not display any of my categories to enable me to select them. And if I click on “Update Options Now” it says: “What’s the point of not showing up any categories at all ?”

Furthermore, when I go to my archives webpage—even though I’ve got the correct permissions on cache folder—it just says: “Could not open cache file years.dat”

Does anyone know what the problem here might be?