Installing the wrong driver can cause conflicts. For example, a mismatched Wi-Fi driver will show “No connections available” even though the hardware works fine.
If your volume and brightness shortcuts do not work, it is a software sequencing issue. You must install the Sony Shared Library, Sony Notebook Utilities, and VAIO Event Service in that exact order, rebooting between each installation. Unknown Devices in Device Manager drivers sony vaio pcg 71911m drivers
Right-click the Windows Start button and select . Installing the wrong driver can cause conflicts