Hi,
Try the following.
Download MiniTool Partition Wizard Home Edition.
Select USB stick, and delete the partition.
Create a new partition - FAT32.
Apply and close Minitool.
Download PLoP Boot Manager: http://www.plop.at/en/bootmanagerdl.html
Unpack.
Start unetbootin-windows-585.exe - and select ISO and PLoP’s file called “plpbt.iso” and write to usb stick.
Then download - YUMI – Multiboot USB Creator.
Start it, select USB stick.
Then select the ISO you want to write to stick.
5.
Insert usb stick into PC that will not boot or write correctly from USB stick and check if it works…
Crossing fingers 
/ Stig Henning
