Weird... it seems you don't have an Inbox. How long has this been going on for? Did you have stuff in there before or did it just never work? I can easily fix it, and setup the proper folders again, but if there's stuff in there that's been lost, I need to go recover backups. Also, the "Incoming!" folder... did you make that? It seems empty, but I wonder if the exclamation mark might be screwing something up maybe.
EDIT: I just looked at backups, and even 6 weeks ago (as far back as backups go) there was nothing in the Inbox, so there's nothing to recover. I've gone ahead and manually setup the missing folders, so hopefully it'll work now. If it does, and you've had this problem since the new server went online, then it was probably just a glitch in my mail migration scripts and nothing to worry about.