Windows 10: Setup now requiring EFI

I corrupted my win10 install with a bad driver update. I updated 5 drivers at the same time, Ya, I know bad idea.
So I pulled out my USB stick with an older win 10 iso on it. I have used this version twice before.
I booted to that USB stick,and started the win10 install. I reformatted the win 10 partition for a clean install, as well as the little 462mb partition.
Note the SSD that had win 10, also has Win 7, and win 8.1 bootable partitions.
Now I get "The selected disk has a MBR partition table. On EFI systems, Windows can only be installed on a GPT disks."
I have never had this before during an install.
My system is a custom built machine, with a Asus P8Z77-V Deluxe MB. I have not made any changes to any MB settings in over a year.
What can I do to reinstall win 10?
thanks

:)

 

Converting from bios (legacy) to uefi - How?

Sorry, but I don't think this is possible.

(U)EFI --> GPT partitioning scheme, using an EFI boot loader

BIOS --> MBR partitioning scheme, using a volume boot loader in the bootsector of the active partition

In order to change from MBR (Master Boot Record) to GPT (GUID Partition Table), it would be required to reformat the hard drive. So upgrading an existing Windows 7/8.1 to Windows 10 would give you the exact starting point setup: either BIOS or EFI.

If you want EFI, you need to boot-up in EFI mode; you may need to activate that in your EFI (BIOS) setup. Most EFI implementations include a boot selection menu by pressing one of the function keys after turning the computer on. Something like "F9 for boot
selection menu" or so may be written somewhere in the EFI/BIOS setup.

Using this boot selection menu, you may also be able to choose either a BIOS (often called "legacy") or a (U)EFI start from one and the same media.

The installation media would have to include an EFI boot loader for it to work.

The Windows setup will only allow you to partition and install on a GPT partition if you booted in EFI mode.

Tte WIndows setup will only allow you to partition and install on a MBR partition if you booted in BIOS (EFI CSM) mode.

If you are willing to repartition+reformat your whole drive, go ahead and boot the Windows 10 Insider Preview DVD (burned from the ISO) in EFI mode and create a new partition to install it onto. Make sure you leave empty space for reinstalling Linux later
on.

Provided your EFI implementation is working correctly, you would be able to select either Windows or Linux from the boot selection menu. Alternatively you could install GRUB2 as your standard EFI boot selection and choose which OS to start using GRUB2.

Be adviced that not all Linux distributions support SecureBoot well. You may give it a try though (be ready for pain!) and install Windows on EFI+SecureBoot, and then install Linux using Shim as the Linux bootloader, which will let you secureboot Linux as
well.

I hope that answers your question.

 

EFI partition delete issues and restoration

If I delete the EFI partition accidentally in Windows 10, how do I setup or manage or restore the EFI partition?

 

When you boot from the Windows 10 USB do not select the option that says UEFI USB. Select the option for just plain USB. This is when you are selecting the device to boot from before the computer actually boots from anything.

 

Above may not work - not all BIOSes give option for eufi USB or MBR USB startup.





In any case, you should use latest version using

Windows 10

Also make sure bios is set to legacy bios install.