While in safe mode with network, open the device manager. Expand the USB devices, and you will see a few USB root hubs listed. You can right click on them and go to the properties-->power, and see if and what devices are attached to them. Your mouse and keyboard will be attached to one of them. Uninstall each USB root hub, saving the one your mouse is attached to for last. Once uninstalled, reboot the computer. They will reinstall on restart and rescan for hardware that is attached.