Edit: Please read post 4! I don't know what's wrong here. 2 week old MBA. App Store was really sluggish at first (constant beachball) but would download or update Apps after a little while. Now, I cannot download or update Apps at all. I've tried disabling certificates as some posters have suggested, to no avail; I've also tried deleting the App Store cache, again to no avail. Any suggestions? For reference, this is what I see when I try to download/update: Just a constant ticker in the top left, which stays there until I go to another page or close the store.