New install of v10.0. I've right-clicked the tray icon, gone to Settings->Notifications and unchecked everything it would let me. I've closed and re-opened the client from the tray icon. Popup notifications still run every time a job starts or finishes. This doesn't happen on our production server running v9.9.

Does it happen even with the client closed? If not, what do you have in the Client Events tab of the Client Settings on the File banner?