I'm having some strange issues on a used Mac Pro (cheesegrater) that I recently acquired. It seems like it won't recognize USB-drives of any sort. I've had problems with all of the following: Generic USB Thumb-drives, LaCie external USB hard drives aaaaand my iPhone 5. Whenever I connect either of these the OS simply doesn't recognize them and does not respond as expected. Ie: connecting my iPhone 5 (Not jailbroken. Original cable) will not make it show up in neither iTunes nor Image Capture or in any other apps that should be able to see it such as Lightroom. It does charge though. Connecting a Thumb Drive results in nothing.
It makes no difference whather I'm using the USB-ports on the front or the back or the "second-hand" keyboard USB-ports.
Curiously I'm using an Apple USB keyboard which works just fine and plugged into one of the keyboards USB-ports I have a logitech mouse which is also behaving fine, so this seems to be an issue with recognizing USB volumes first and foremost.
I'm running the latest version of Mavericks on a mid-2010 Mac Pro.
Edit: I got a tip on another site that this might have something to do with broken permissions, so I did a repair persmissions in Disk Utility and ran through the maintenance scripts of Onyx for good measure. It now seems like the USB-ports on the back of the machine are working while those on the front are still borked unresponsive.
diskutil list
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