Sir first of all thank you so much for replying. 
Sir I'm using SanDisk Ultra USB 3.0 (14 Gigabyte Memory) to install QNX 4.25 ISO file on PXIe-8130 Embeded controller 
using PXIe-1071 Chassis. I made QNX 4.25 ISO file using MagicISO software and then I made USB Bootable using XBoot 
Software. I tried other softwares (i.e. UltraISO, Rufus, PowerISO etc.) to make it Bootable but it always failed, Only 
XBoot did it successfuly.
Now, when I plug-in USB and Boot system from USB, it stops just after a few initial steps, means, Screen shows option to
 select Operating System to be installed. QNX 4.25 is also showed there. When I click on it, it simply hangs up there 
and following message is shown on screen:
 
"B kbd Unable to open system initialization file: corrupted file system detected" 

I am in doubt that may be I'm committing some mistake in making USB Bootable.
Please guide me in the light of your greater experience please.
Thanks in advance.