Windows 10: No bootable device found after linux install

Hello,
So, I've had a pretty big issue today. I installed Debian as a dual boot with win10, and it worked! The only problem was that I didn't have access to either root or sudo. In order to fix that, I booted into Ubuntu because my Debian live image logs out after a few seconds and mounted the partitions that Linux was installed on. My part table is below:
/dev/sda1 - EFI
/dev/sda2 - Microsoft Reserved
/dev/sda3 - Microsoft Basic Data
/dev/sda4 - Windows Recovery
/dev/sda5 - Windows Recovery
/dev/sda6 - Linux /root
/dev/sda7 - Linux Swap
/dev/sda8 - Linux /home

I believe I mounted sda 1, 6, 8, and by mistake 5. I ejected the device (by accident without umount) and then tried to boot. My computer is a dell, and on boot I immediately got the device recovery menu. I booted into the F2 UEFI menu, and saw that my boot options list had gone from Debian, windows boot menu, and my hard disk, which was labelled as UEFI (some numbers here, sorry).

I've tried everything I can think of, including hours of non-stop googling. I removed and formatted the partitions Linux was installed on, and then reset the MBR from a windows live CD. I don't think it went through, because there is still no option in the F2 menu for device boot unless I plug a device in. I believe windows is still there, but there is no way for me to access it.

I can't access it through a Debian live image, because the one I installed from had an issue where as soon as I logged in, it would immediately log me out.

I don't want to do an recovery from the live disk, because I have hundreds of applications on my computer that would take me forever to reinstall.

I'd love some help with this issue, because I've been tearing my hair out and can't find anything online to try to solve it. I've had to do all my research from my phone, so I might have missed something.
Thanks,


:)

 

No Bootable Device Found

Hi,

I have a persisting problem with my operating system, which has already been repaired TWICE by a professional.

Every now and then my laptop will just boot up with no bios and a "no bootable device found" error message, and when I put in a USB with the right version of windows 10 to repair this can't even reset the laptop let alone repair/ or patch the corrupt files.

The first time this happened the laptop ran out of battery during an update, which was fixed professionally. However, the penultimate time it happened the laptop ran out of battery yet wasn't installing or downloading any updates. this time, the laptop was
shut down properly, with no updates running and still plugged into the charger (I never let it run out of battery fully now).

I am obviously unwilling to pay again to get another repair done on a laptop that has in total cost well in excess of £1000 with repairs.

Windows, please tell me a solution to this problem that keeps persisting. There are no viruses and laptop has not been damaged in anyway.

Many Thanks.

Moved from: Windows / Windows 10 / Install, upgrade, & activate

 

No Bootable Device Found

It sounds like Windows 10 is not properly installed.

Go to a working computer, download, create a bootable copy then perform a clean install.

Step 1: How
to download official Windows 10 ISO files

Step 2:

• How to: Perform a clean install of Windows 10

 

You are basically going to have to rebuild your EFI System Partition. Similar to this:
Windows 10 Windows 7 Dual Boot - Can it be done Solved - Page 7 - Windows 10 Forums