This is a common problem with window 8. After the upgrade to window 8 from any other window or sometimes window 8 itself download & install the update available...
As a result window 8 WiFi driver may corrupt. This can also result in stop working of WiFi. Sometimes it also notice that WiFi button also stop working...In this case we recommend that you will re-install the WiFi Driver again.
If you buy the laptop/computer with pre loaded copy of window 8, you can locate the WiFi Drivers in "Window Drive". Most of the time it is Drive C:
Window Drive (Usually Drive C:) >>>> SWsetup >>>> Drivers >>>>RaWLAN
Run the setup.exe and restart the computer and you are done.
In case you had upgraded your computer to Window 8 you can find your computer or laptop driver here:
The above link is for HP USA Site. If you are living in some other country, you can go to HP global site Now select your county.
Click on Support & Drivers, Must on the 1st page. Enter the Model Number or Product. Download the WiFi Driver, Install and Restart your computer.
Sometimes there are more than 2 WiFi Driver. You have to select from the two. If one not work then second will work surely.
For more information & help you can see the below article.