Take all the files on a USB, copy them to a "vault" folder and a "viewable" folder, delete them from the USB after verification, and periodically delete files older than X days from the "viewable" folder.
Take all the files on a USB, copy them to a "vault" folder and a "viewable" folder, delete them from the USB after verification, and periodically delete files older than X days from the "viewable" folder.