Question Glitched boot order in BIOS on Acer Nitro AN515-55 ?

[valbrenz]

Hello folks, I've installed a Linux based operating system with a bootable usb, and I'm now trying to setup dual boot with Windows. I must've messed up the laptop's USB ports since now, whenever I plug in the working bootable USB, the boot order in the bios glitches.
It appears to be empty and the only entry is a blank option. If I press f5 or f6 to move it up/down some glitched names appear, and those are not my bootable devices.

I haven't made any significant changes to the system except switching from RAID to AHCI because linux wouldn't see the ssd otherwise.

I confirmed that the USB stick is working, and what makes me think that this is an issue related to the ports is that I already had this same issue once before and I fixed it by switching ports, but that's not working anymore.

Is there something I can do?

 

[kerberos_20]

boot to uefi shell and wipe boot cache there from your uefi firmware

you can download uefishell from github, in most uefi bioses you can boot it from boot override options

https://kmpic.asus.com/images/2020/12/16/14c3d5de-f7a1-4f7d-9476-951579c51960.png

here two examples

once you enter uefi shell, then use this command to see your current boot entries
bcfg boot dump -b

all boot entries are numbered
to delete boot entry number 2
bcfg boot rm 2

 

[valbrenz]

Thanks for your reply, but I have a bit of a problem going into the uefi shell...
I can't modify the boot order to use the USB with the github download you provided, so I tried looking for a built in way to access the shell from the bios firmware and I found a Boot Mode option (set to 'UEFI' ) that is grayed out and not modifiable. I'm not sure why.
Also the firmware I'm using is Insydeh20 Setup Utility rev 5.0