i used to be able to share my internet connection with my friends by using my laptop as a router when connected the=rough wifi or LAN, somehow the "turn on" link just went grey and i'm not able to turn it on anymore.
i tried uninstalling vaio control centre and installing it again, but this time when i turn it on it displays the message, "turn the WIRELESS switch on the vaio to ON, and then try again"
Welcome to Sony Community! Most of the time re-installing the original driver fixes the issue on the laptop, it helps refresh the driver installed on the computer to communicate easily to the hardware. So the suggested fix that BrianP put here could fix the issue.