Another problem with starting my laptop!

[Taro]

Hello i recently installed a windows 7 os on my laptop that used to have win10 pro Just because i like w7 more. The problem is when i installed win7 a error menun popped up with the error code: 0xc0000428
Its says cant verify file. Well i be honest with you guys this is not the legit windows version. BUT i finally found my windows serial key and downloaded the legit version but cant get it working! Went to the boot menu set USB to 1st palce when i plug in usb nothing happens ;( Same with disc. Now i tried somethink else and when i start my laptop i see a menu saying: choose your operating system... I get to choose win7(when clicking on it i get the problem)OR win10 but when i click win10 it loads some things and i egt stuck in a black screen i only see my mouse cursor nothing else. I waited 2 hours nothing happened. Help me please need my laptop working!

 

[RaDiKaL_]

You need to change an option in your BIOS, for Windows 8/8.1/10 there's an option that needs to be enabled (often times it says OS Windows 8 or Secure boot, but this varies from BIOS to BIOS) and most likely that option is enabled which you need to disable in order to be able to install Windows 7.

To have some idea you can look at this link:

https://aps2.toshiba-tro.de/kb0/tsb2c03f80002r01.htm