When trying to patch a HP DL380 G7 Server to the latest service pack (SPP) I ran into a problem creating a valid USB Boot Key! When trying to boot the server using the USB Key it seem that I was missing some files when I build the USB Key using Rufus latest flavor!
I found the perfect tool to make this work. Download and install UNetbootin Diskimage to copy the bootable .ISO over to the USB Flash Drive.
NOTE: Not working using 32GB+ USB KEY!
First thing is to format your USB Flash drive to FAT32!
Once properly formatted run the UNetbootin tool to create the SPP USB Flash drive.