PocketWizard Mini-Flex Canon 60D
Sounds like you may have a usb conflict if it's not recognizing when plugged in. Have you tried different usb ports. Also you may want to plug them in and check device manager for conflicts. Also you can try deleting it from device manager and then hit refresh to have windows re-detect and reinstall the devices.
If you have the chance try them on another computer. That should definitely determine if it's a unit problem or pc problem. One other thing I just thought of you may also be conflicting with another usb device or some other software. Be sure to try unplugging all other usb peripherals and try booting clean but temporarily turning off all running startup programs using msconfig. I once had another issue and it was due to the usb dongle for a music software app I use.