Even with the printer disconnected from the USB port/hub, the driver is still installed but just inactive. Try this:
disconnect printer from USB -->
Control Panel -->
Add/Remove Hardware -->
Uninstall/Unplug Device -->
Uninstall Device -->
check the "Show Hidden Devices" checkbox -->
then remove the references to your printer.
This should, at the very least, force a redetection and reinstall of the printer drivers (if needed) when you reconnect the printer to the USB port.