Hello. I want to boot my computer from my USB flash drive because I have an ISO file burned onto it. I had to change the boot mode from UEFI to legacy. The only way to do that on my computer is to remove the EFI system partition. I tried using diskpart but there was a problem with the MBR. So I used the Easeus partition master to delete the partition. And it said I had to restart the system to delete the partition. It bought me to a screen that said that said the partition was successfully removed. But instead of my lock screen showing up a screen that said "no bootable device" showed up. I pressed ctrl+alt+delete, alt+F10, and a variety of other key combinations but my computer won't boot. Can you please help me?
No bootable device
- Thread starter Ethan
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The screen looked like this:
https://www.google.com/imgres?imgur...5nOAhWKsh4KHTOnA_sQMwggKAMwAw&iact=mrc&uact=8
https://www.google.com/imgres?imgur...5nOAhWKsh4KHTOnA_sQMwggKAMwAw&iact=mrc&uact=8
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Typically, on most computers that is a BIOS setting that you can toggle on or off often by just disabling "Secure Boot"
Why did you have to change it?
That means that you likely deleted the partition that contained your boot configuration data, so it is little surprise that you are getting the error message regarding a bootable device.
What ISO did you write to the USB drive that you are attempting to boot from.
I do not believe that doing anything to your hard disk even if you managed to delete every partition and formatted the entire unallocated space that, that would result in changing you systems UEFI configuration.
That is BIOS dependent and independent of anything on the hard disk or even if there is a hard disk.
Thank you for your response. My computer is the Acer Aspire Switch 10 with BIOS v1.06. Secure Boot is already disabled but there is no switch for UEFI/Legacy BIOS. I am attempting to boot from the Elementary OS 64-bit ISO. Also, in the Boot tab in the BIOS, for the boot order, it only lets me select which order to boot from, it doesn't let me choose what to boot from. Yes, I deleted some other partitions as well as the EFI system partition to test diskpart. Diskpart wouldn't let me delete certain partitions. I can access the BIOS but nothing else. How do I get Windows to boot normally?
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It seems you have a basic misunderstanding of how these systems work. Most of what you mentioned in your first post is just not correct.
Booting a USB drive in UEFI mode has nothing to do with the boot drive but completely controlled by the bios and its settings. UEFI does not use MBR but does use the GPT hard drive configuration.
You can recreate the EFI partition and replace the boot files if that is what you want to do. It will have to be done using Diskpart.
DISKPART> create par /?
Microsoft DiskPart version 10.0.10586
EFI - Create an EFI system partition.
EXTENDED - Create an extended partition.
LOGICAL - Create a logical drive.
MSR - Create a Microsoft Reserved partition.
PRIMARY - Create a primary partition.
Booting a USB drive in UEFI mode has nothing to do with the boot drive but completely controlled by the bios and its settings. UEFI does not use MBR but does use the GPT hard drive configuration.
You can recreate the EFI partition and replace the boot files if that is what you want to do. It will have to be done using Diskpart.
DISKPART> create par /?
Microsoft DiskPart version 10.0.10586
EFI - Create an EFI system partition.
EXTENDED - Create an extended partition.
LOGICAL - Create a logical drive.
MSR - Create a Microsoft Reserved partition.
PRIMARY - Create a primary partition.
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If your system had UEFI boot enabled you should have been able the USB drive if it had been configured correctly, as Fat 32. It may show a boot device menu where you would need to select the drive with a UEFI designation or a Windows Boot Manager.
I checked a User manual for your device and did not see any diagrams of your Bios selections. Each Bios is different in how it presents the UEFI options. But Secure Boot being disabled may not also disable the UEFI boot. There may be some setting regarding compatible OSes.
Do you have any USB drive which should be bootable, such as a prior restore or media version?
Does EaseUS give you the option of replacing the EFI system partition or even give you the option of formatting a small partition as Fat 32? If you can get that done then you can boot into some recovery media or install media and restore the boot files.
I checked a User manual for your device and did not see any diagrams of your Bios selections. Each Bios is different in how it presents the UEFI options. But Secure Boot being disabled may not also disable the UEFI boot. There may be some setting regarding compatible OSes.
Do you have any USB drive which should be bootable, such as a prior restore or media version?
Does EaseUS give you the option of replacing the EFI system partition or even give you the option of formatting a small partition as Fat 32? If you can get that done then you can boot into some recovery media or install media and restore the boot files.
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Doesn't that device have a reset button that supports returning to factory settings? Assuming that it doesn't rely on one of the partitions that you have deleted.
Getting hard to keep track of exactly what your objective is....
Do you want "Windows to start normally" or do you want to wipe the device and install an OS, that apparently isn't UEFI compatible?
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If that OS, and I have no knowledge of it, is not Secure Boot capable you probably not be able to dual boot it. If it were I would not suggest doing so.
If you are wanting to wipe Win 10 from your system and install the OS it sounds like it will be a Legacy install. If it is will it boot and run on a GPT drive? Your Bios setup will have to be your responsibility as to Legacy or UEFI. You might be able to find answers on an Acer group or take pictures of your Bios options and attach.
If you are wanting to wipe Win 10 from your system and install the OS it sounds like it will be a Legacy install. If it is will it boot and run on a GPT drive? Your Bios setup will have to be your responsibility as to Legacy or UEFI. You might be able to find answers on an Acer group or take pictures of your Bios options and attach.
