My HP's wifi isn't working!!!?

[Liana]

So I've has my computer for maybe 2 years. It's worked fine but now suddenly the wifi has stopped working. No networks appear at all and it tells me when I troubleshoot it, it tells me to plug in the Ethernet cable. The internet works for everyone else in my family. I've tried actually connecting the computer to the router with the cable, and it works. I've restarted my computer a million times, and I've used system restore three times. What should I do?