I can access the USB drive via the admin menu "File Explorer", or admin login, or either of two users I've created, or the anonymous user.
Problem is only four icons show up across the bottom (thumbnail, create folder, upload file, eject USB). The check boxes by each file name no longer do anything. There is no icon for deleting or renaming a file. The four icons I see do nothing when I click them.
What happened? It was working fine for months. It seems a firmware change they pushed has broken the USB file graphical user interface.