Wi-Fi not working on a HP/Compaq notebook
If the wifi button is not working on a hp laptop, the problem is overheated chipset. clean your coolers before it fails completely. Other symptoms are malfunctioning USB ports and optical drive. Chipset IC needs to be replaced, or replace a whole MBO.
Another thing you can try:
Download and install HP Wireless assistant. Reboot and open the utility. Try turning on the wi-fi radio there. It the option is unavailable, close the utility, press the button again, then open utility and the option should be available. If it still isn't working than it's the problem I described above..