Grub4dos not working with HP EliteBook 2530p

Question

I've set up a multiboot portable drive with grub4dos.
It boots fine on all machines except HP EliteBook 2530p (and probably EliteBook 6930p).

When I select a boot entry, it gives me a

disk read error 25

and if I set root partitions with respect to their UUID's, it gives me a

file not found error 15.

I'm really stuck and don't really know what else to do since my USB pen drives boot fine.
I don't know why it doesn't boot my external HDD's properly.

What can I do to fix this?

Answer 1

Some BIOS have a bug in their USB driver code. It is quite common. They cannot access any sector past 128GiB (137GB) on a USB drive. Make sure all files are before 128GiB. The easiest way to do this is to ensure that the first grub4dos partition is 128GiB or less in size.