My bad. Of course, I should have used an amd64 iso file. (I forgot that the architecture makes a difference because persistent live drives made with mkusb work in UEFI mode also when made from i386 iso files. But in that case a bootloader and EFI files are provided by the installer.)
I'm trying again with a clean MSDOS partition table and a FAT32 file system.
Code:
file-roller lubuntu-14.04.3-desktop-amd64.iso
I mark and paste from file-roller to a nautilus window /media/OLDFRED (in the pendrive). I want to test 'the GUI way'.
Code:
$ sudo parted -s /dev/sdd print
Model: SanDisk Cruzer Blade (scsi)
Disk /dev/sdd: 4005MB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Number Start End Size Type File system Flags
1 1049kB 4005MB 4003MB primary fat32 boot
$
It works
Lubuntu 64-bit boots and works like it should.
I'll try with a GUID partition table too (and a FAT32 file system).
Code:
$ sudo parted -s /dev/sdd print
Model: SanDisk Cruzer Blade (scsi)
Disk /dev/sdd: 4005MB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Number Start End Size File system Name Flags
1 1049kB 4003MB 4002MB fat32 msftdata
I marked and pasted from file-roller, and after that changed from msftdata to a boot flag
Code:
sudo parted -s /dev/sdd print
Model: SanDisk Cruzer Blade (scsi)
Disk /dev/sdd: 4005MB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Number Start End Size File system Name Flags
1 1049kB 4003MB 4002MB fat32 boot
$
It works
Lubuntu 64-bit boots also with a GUID partition table, GPT.
This is really a simple method, particularly with an MSDOS partition table and a FAT32 file system.