Windows 10: Why can I no longer boot Linux from USB

I have an Acer Swift 5 laptop. After the August Security Update i can no longer boot from my USB hardrive. I am aware that there was an issue with secure boot which I disabled.It seems that it is no longer detecting my USB hardrive to boot from. I remember in the bios there was a setting called Boot mode which was set to legacy to allow me to boot from USB. That setting is now gone and I don't know what to do anymore.Please any help would be great.

:)

 

Boot linux on USB drive

it might just be that your bios doesn't support it, but it should anyway.

make sure you go into the bios and make sure "boot other device" is enabled and try seeing if the usb is listed as an hdd.. as bootable flash drives are usually picked up as usb hdd's and check if your bios detects the flash drive.

 

usb device no longer accessible in Windows

I made a boot USB of OS X Snow Leopard from the real DVD. I had to go through several steps because I don't have a real mac. I installed OS X in a virtual machine and used SuperDuper to perform the format and copy of the OS. It installed perfectly on a customer Mac Book. Now, I no longer have any use for the OS X boot usb, so it was time to format the device. I formatted the usb in Linux and used NTFS filing system. When I stuck the usb flash drive into my PC, only 230mb is available. I wanted to see what was going on, so I opened up Disk Management and it shows 250mb (FAT32) and another partition that's 7.27GB, but it cannot be formatted. What can I do to fix this problem? I'm at my wits end! If necessary, I could post some pictures of whats going on.

 

No boot from USB

As Kyhi mentioned, If you're booting from a USB drive, it doesn't matter what you have on your laptop drive.
How are you pointing to boot from the USB drive, by BIOS priority or by boot menu during POST?
Follow these steps to open the Startup menu when the computer is powered off.

1. Turn on the computer.
2. Immediately press the Escape key repeatedly, about once every second, until the Startup Menu opens.
3. Select the EFI USB drive

PS.: You can only boot as UEFI if the OS is 64 bits. Is your Linux on the USB drive 64 bits version?
Is the USB drive formatted as Fat32?