Installing lts ubuntu from usb

[tech-gamer]

Hi. I putted files inside ubuntu iso files into usb and booted from usb. But it went straight into grub. I did chainloader +1
And it said error: invalid EFI file path

[oldfred]

Is this an UEFI system? What brand/model?
Most use various installers to extract ISO, format flash drive and add boot loader.
If just UEFI you can do that yourself, but have to directly boot from UEFI, not from another grub on hard drive.

If UEFI only, then can just extract ISO with 7-zip to FAT32 formatted drive with boot flag on FAT32 partition.
Will not boot in BIOS mode
UEFI only USB key, just extract ISO ( 7 zip or similar) to FAT32 formated flash & set boot flag.
http://askubuntu.com/questions/395879/how-to-create-uefi-only-bootable-usb-live-media
UEFI only bootable flash drive
http://ubuntuforums.org/showthread.php?t=2299040

Shows install with screen shots. Both BIOS purple accessibility screen & UEFI black grub menu screen
https://help.ubuntu.com/community/UEFI


Lots of info on USB boot for installing
https://help.ubuntu.com/community/Installation/FromUSBStick
Ubuntu install guide - multiple ways to create live installer to flash drive
https://help.ubuntu.com/community/Installation
Updates for ISO to USB.
https://help.ubuntu.com/community/Installation/iso2usb
Updates -Instructions to make a boot drive, that boots both in UEFI and BIOS mode
https://help.ubuntu.com/community/Installation/iso2usb/diy
https://ubuntuforums.org/showthread.php?t=2299040

[oldos2er]

Did you "burn" the ISO to the USB flash drive? Simply copying it there won't work, nor will extracting the ISO and then copying.

https://help.ubuntu.com/community/BurningIsoHowto

Please provide some basic information about your hardware specs, any currently installed OSes, and whether your system uses UEFI or MBR.

[TheFu]

Great! Is that what you wanted or is there some question?

Copying ISO files onto a USB is not sufficient to make it boot. Perhaps if you explain exactly what you did, someone could help?
https://tutorials.ubuntu.com/tutorial/tutorial-create-a-usb-stick-on-ubuntu might be helpful.