I've had USB warning issues before but after upgrading I have 5 of them and they won't go away. If I click OK they come right back. I've tried unplugging all of my USB devices and they're still pop up. I've tried the usual restarting and repairing permissions. Any suggestions? I'm running a 2.66 Dual-Core Intel Xeon Mac Pro with 8gb ram. Typical USB items are 3 printers(1 usually on), mouse, powered USB hub, and iphone dock. The computer and other devices are plugged into an APC XS1500 backup batter and line conditioner.