I recently brought HP Laptop (IDK which one), for my business purpose to modifications of site likes(http://usawriters.org/ ) which had Windows 7 genuine installed, and yesterday there was Upgrade to Windows 10 balloon.The problem is the Laptop now turns on with a black screen, no cursor, nothing, as far as I am aware it's skipping the BIOS screen, so if it's anything like Windows 8, it's not a real hard boot, obviously.There is no BIOS setting to use even the Recovery disk. How to fix my laptop.
I think you'd better contact with your direct vendor and HP first to find solution of recovery of the Windows 7 preinstalled. Besides that, I would make an Windows 7 installation media such as USB drive or burned DVD+/-R disc with which to boot up your computer and make a refresh installation. After Windows 7 successfully installed, pay visit to HP websites where you could search the proper drivers or contact with HP support.
You can download the Windows 7 ISO from the above website, the product key might be placed the back cover of your laptop, or you might need to remove the battery to find it. Anyway, your further feedback is welcome, and I wish you good luck.