If you are a Sony VAIO laptop owner then you should wait a few more days before upgrading to Windows 10, as the upgrade can cause a number of issues on your laptop. Sony posted a warning on their website that VAIO laptop owners should wait until new drivers become available.
Although Microsoft is offering the Windows 10 upgrade, it is strongly recommended that you wait to install it until the drivers & installation instructions are available for your VAIO PC. Bookmark this page and check back here before upgrading to Windows 10 for the latest information for your VAIO PC model.