1 February 2013, 09:31
Sometimes one of my USB memory sticks just stops working in that it disappears from Finder. Pulling it out and reinserting it does nothing.
The solution is to plug it into a different USB port. Somehow this means it can be sensed afresh, and mounted properly.
If even this can’t fix things, open Disk Utility (in the Utilities list of Applications) and right-click its entry there, selecting Open.