does a usb flash drive suffice to install the expansions?

This is the second time today to start a new thread when you actually have a http://www.gamesas.com/index.php?/topic/1142379-oblivion-goty-360-4gb-cant-install-expansions/. Please use that instead.

Yep. If you already have a thread open dealing with this topic, there's no reason to start another one.