I came across a strange USB problem on my 11.6" ultimate the other day when transferring one of my small Aperture libraries (~14GB) from my MBP. I formatted an external 500GB drive (Mac OS Extended Case Sensitive Journaled) and copied my Aperture library to it. I then ejected the volume and hooked up to my MBA and started the copy process back (both times using Finder). After about 200MB, the copy froze and I got a message about disconnecting my USB drive incorrectly. Yet, in Finder, the volume was still mounted. I attempted to repeat the copy but this time from Finder (cp -v). Once again, the copy stalled at a given point and I got the message about disconnecting my USB drive incorrectly. Once again, in Finder and on console (df) the volume was mounted. However, an ls from within the original volume mount failed with an error that the mount point no longer existed (obviously the drive was unmounted and remounted for this to have occurred). I repeated the test with a USB key, this time formatted without case sensitivity. I got the exact same results and was unable to copy my Aperture library via USB. To make matters even move obscure... I really needed the library off of my USB device (didn't have the time to copy over the network nor did I want to work off of it) so I attempted a tar off of the key via the following process; $ cd /Volumes/USB $ tar cvf ~/Desktop/library.tar library.aplibrary This WORKED and I got a VALID tarball containing my ENTIRE Aperture library. I extracted the tar and went on my way. Anybody have any ideas here? Could somebody with another MBA repeat a similar test and post up your results? I'm wondering if this is some sort of driver/chipset problem or something isolated to my laptop. According to Software Update, my system is fully up to date.