operating system not found and cannot access bios

I have a new Sony Vaio SVP132A1CM. Not liking Windows 8.1 and wanting to revert to Windows 7, I followed the instructions in the following article.

Commence Installing Windows 7 - How to Uninstall Windows 8, Install Windows 7 on Your PC | PCMag.com

I clearly made some sort of error as on attempting to boot from my Windows 7 Installation Disc, all I get is

'Operating System Not Found'

I have tried hitting F2 or F10 on boot but I get nothing. I can hear the drive, and the computer is brand new. I assume that somewhere in the process I have managed to erase everything including the OS. I have an external CD drive and the Windows 7 Home Premium disc..........

Hi

In newer SONY laptops with UEFI firmware, you won't be bale to access BIOS by pressing F2. You can try the below steps instead.

1. Power off the laptop.

2. Instead of pressing the "Power Button" to turn on, press the "Assist" button.



System will be powered on and a menu will be displayed. From there press "F2" to enter BIOS.

3. To install "Windows 7" , you need to disable "SecureBoot" , enable "Legacy" mode and clean the current GPT partitions using DISKPART. However do this only if SONY provides drivers for your model. If SONY is not officially listing any Win7 drivers, you will have a hard time hunting down the drivers. Also you will loose special key functions like adjusting brightness etc.

Anshad, thanks , that's progress, I am now in the Bios. As per the instructions on the website, I have disabled secure boot and enabled legacy.

I have also secured and saved ALL the Windows 7 drivers. They were available on the Sony site as the laptop can be bought with Windows 7 ( don't ask me why I didn't do that!?)

What I have not done is ' cleaned the current GPT partitions using DISKPART'................can you can explain how I do that.

Thanks

Paul.

Hi

You can open a command prompt from the Windows installation disc by following the below guide.

Command Prompt at Startup

Then refer step 3 and onward of the DISKPART tutorial : Disk - Clean and Clean All with Diskpart Command

What you need to use is the CLEAN command ( not CLEAN ALL ). This will wipe the GPT partition structure entirely and then you can exit DISKPART continue with installation.

Hi Anshad, I followed those instructions and began the installation, which has now failed twice, the prompt being:

Windows cannot install required files. Make sure all files required for installation are available, and restart the installation' I am trying to install from my 64 bit Windows 7 Home Premium disc.

Windows cannot install required files. Make sure all files required for installation are available, and restart the installation' I am trying to install from my 64 bit Windows 7 Home Premium disc.

Usually that message indicates a disc read error. I would recommend creating a bootable USB flash drive and using it to install Windows 7. Detailed instructions are covered in the below tutorial.

USB Windows 7 Installation Key Drive - Create

Make sure to plug the USB drive to a USB 2.0 port when installing.

Well I tried that, followed all the instructions and I'm still not getting anywhere, in fact whilst I can still get into the opening diagnostic screen and bios, the windows installation disc wont even boot now. I was warned that this was rather a complex procedure, and it certainly is. I now have rather a nice piece of folding metal that has some lights on it!

Hi

Don't be panic. If SONY listed drivers for "Widows 7" , your machine will support it.

If memory serves correctly, SONY BIOS won't list USB flash drives for boot by default. After preparing the USB drive as per the guide, plug it in to a USB 2.0 port and enter the BIOS setup. Probably in the boot order changing screen, you will find an option to enable "External Device Boot" which is generally set to "Disabled" state. Make sure to enable it and change the first boot device to "External Boot Device". Hopefully Windows setup will load from the USB. Once the file copying is completed and system is restarted, enter BIOS setup again and disable the external boot device support. Otherwise system will boot from USB again instead of HDD.

I would suggest watching the below video guide ( language is not English so ignore the audio ).

https://www.youtube.com/watch?v=2le8w9CzZ2U

Which settings in BIOS are available for UEFI, CSM, Legacy? Take a picture if necessary with all choices expanded.

Where did you get the Win7 disk and how is it burned?

Download the latest official ISO for your licensed version and burn to DVD or flash stick using Windows 7 USB-DVD Download Tool.

At reboot tap the Sony F12 key to boot the disk or stick. Follow the steps in Clean Install Windows 7. If it fails report back verbatim error message and step at which it fails.

Other steps here for Overcoming Windows 7 Installation Failures - Windows 7 Help Forums

Win7 is a driver-complete OS so drivers are never an issue as most are provided via Windows Updates. The few then missing can be imported from your OEM's Support Downloads webpage, or found via search. I've never seen one not be found in tens of thousands of installs we've helped with here.