Button Start -> Settings -> after the Control Panel -> System; click System Options -> then Hardware -> Device Manager; in the box labeled "Device Manager" select big yellow circle with a black exclamation mark; Select from the menu Action -> Delete then; in the "Confirm Device Removal" must authorize the removal of the keyboard by pressing OK; close the Device Manager; in the window with the name of the System Properties Hardware tab, click Install required equipment; in the window titled Found New Hardware Wizard should press Next; After a brief search of equipment your keyboard should be "found" (including indicator Num Lock); after these actions should be a window Changing the system with the text message "finished installing new devices." the last step is to press in the New Hardware Wizard Done.