Error:Windows has allocated a drive letter to the U3 drive that is already taken by another drive on your machine or there are no more drive letters available on this machine. Try disconnecting any network drives that you have connected to your computer and restart U3 by double-clicking LaunchU3.exe or the U3 System CD-ROM icon. __Once the U3 Launchpad is running, you can reconnect the network drives,(I am the administrator).
I may have an answer for this issue.
I downloaded and ran as administrator a free utility call “usbdeview”. It allow me to see all of my usb device. I
used it to uninstall all devices that were not currently connected to my computer. I also uninstall some of the
generic usb hubs it was showing. After rescanning for hardware change and after unplugging and replugging my usb
keyboard back in I was able to get the U3 launcher on my cruzer to work correctly.