If you are trying to install fresh over a Hp/Dell prebuilt unit and it is giving you that flashscreen you will have to contact them,
No-one here will advise you how to crack/bypass security on systems,
its against the Terms and conditions we signed up to when we joined Toms, and you should not post requesting us to,
unless you can speak to a moderator and satisfy them you have a legitimate case, then this post will be locked and you may be banned,
Moto