Follow the instructions in this link and try to delete the device this way.
Often time when a driver doesnt install correctly it wont uninstall correctly either.
This will show all devices that have been hooked to the system past and present.
The past or unplugged devices will be light gray.
Delete all of the ones that you know wont be used anymore including the one that you are having trouble with.
Be certain that the device is unplugged (both plugs) and reboot.
Then try to install the software.
Other things to try that have helped me with USB problems.
Some times when it is time to introduce the device after driver install I have had to power on the device and then insert the USB plug. Other times I have had to do the opposite.
Also check your BIOS for USB settings. If the use legacy support is on try it with it off and vice versa.
Most times it should be on as most keyboards and mice want it that way.
Also in the BIOS if you have the option be sure that it is set to USB2 and be sure that with the manual you are using a USB2 connecton.
Some computers have both USB 1 and 2 connections. They look the same but the throughput is different.
USB2 devices will usually work in a USB1 connection but not the other way around.
http://support.microsoft.com/kb/315539