If the button stopped working recently:
Because Sony sold its VAIO brand in 2014, official driver support has become more limited for older models. Drivers and Software updates for Personal Computers - Sony
If you own a Vaio laptop made after 2014 (by Vaio Corporation), visit: Note: Newer Vaio laptops may not have a physical Assist button; they use Fn+something.
You need the exact model number to download the correct driver. It is usually found on a sticker on the bottom of your laptop (e.g., SVF1521DCXW , VPCF136FM ).
Surprisingly, some Sony driver mirrors still exist. Try this direct pattern:
If you are having trouble finding drivers manually, Sony created an automated tool.
Users can troubleshoot these issues by: