Windows 10 is still rolling out for free to current Windows 7 and 8.1 PCs owners, but Sony is telling owners of its older VAIO PCs that is is not advisable to download and install that upgrade yet for those products.
Sony sold off its VAIO PC unit in 2014 to a Japanese investment firm, but it is still offering owners of its previously-released PCs online support. In a post on Sony's site, it says:
"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."
The site also has a schedule of when those drivers will be released. For VAIO PCs with Windows 8.1 installed, Sony says the drivers will be made available in October, while its PCs with Windows 8 will get those drivers in November. At the moment, there's no schedule for when drivers for Sony's PCs with Windows 7 SP1 installed will be released.