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Can't Change From Legacy Bios To UEFI

Posts: 2
Registered: ‎24-04-2016

Can't Change From Legacy Bios To UEFI

Hi, I recently fixed my Acer ES1-111M-C3CP, after accidentally removing its software. I installed Ubuntu 14.04, as that was the only software I could install. in the process of doing this, I changed the boot mode from UEFI to Legacy. Now, I can't change any settings, apart from the date and time. I shall provide pictures. I just want to know if it's possible to return to UEFI boot mode. Thanks in advance!
Posts: 236
Thanks: 88
Fixes: 12
Registered: ‎24-11-2015

Re: Can't Change From Legacy Bios To UEFI

I don't know for sure but I suspect this is because the BIOS is checking the partition table type on the hard disk to see if UEFI can be enabled. I suspect that the your hard drive has a MBR (Master Boot Record) legacy partition table which is being detected by the BIOS and preventing UEFI from being enabled.

For UEFI to boot a hard disk it must have a GPT (Guid Partition Table) partition table.

Rising Star
Posts: 110
Thanks: 7
Fixes: 1
Registered: ‎24-07-2014

Re: Can't Change From Legacy Bios To UEFI



Well, we I'm guessing we need to change the BIOS boot from Legacy (or some other words like CSM Boot) to UEFI, but it's not possible.


According the booting section of , we could enter the efi boot by pressing "F2 at the boot splash screen to enter the EFI setup, then select the Boot tab."


If that doesn't do anything, I would just take out the cmos battery and put it back on - which should reset any BIOS configurations and return the BIOS back to factory settings.


Scratch that, I believe mikelahey is right, a model of an Acer laptop is designed for you to have to install efi Windows 8 (with the GPT table as I'm pretty sure MBR wouldn't work).

Though you ought to ask over at the Acer forums where someone there can help you specifically for their products. I myself don't own an Acer laptop.

Posts: 2
Registered: ‎24-04-2016

Re: Can't Change From Legacy Bios To UEFI

So I changed the partition to GPT, but now it just comes up with a black screen saying:

'Error: no such partition.

Entering rescue mode...

grub rescue>'

Am I supposed type some sort of command here? I know I changed the partition and that's why this is happening, but now I can't boot anything...

Posts: 6,347
Thanks: 96
Fixes: 4
Registered: ‎08-01-2008

Re: Can't Change From Legacy Bios To UEFI

Have a read here.

Insert an EFI only Ubuntu USB stick and see what boot options you get.

Call me 'w23'
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