If the EFI Bootcode points to incorrect block of the disk, so the boot services terminates.
HP-UX or the EFI's NVRAM image is wrong..we need to detect the problem and rectify it.
How to do that:
1. After server restart using EFI enter in "boot option maintenance menu"
2. select "add boot option"
3. select partition written like "IA64 EFI [Acpi(HWP0002,100)/Pci(1|0)/Scsi(Pun0,Lun0)....]
4. "select file or change directory" message will appear now
5. Using narrow keys select directory <EFI> and enter inside
6. Using the menu try to find the "HPUX.efi" and select that file and hit enter.
7.Now it will ask confirmation to save (Enter yes) : It will save the new option to NVRAM.
8.Then navigate to the starting EFI menu where boot devices are listed and there will be option "HPUX" or similar just hit enter on it.
9.That's the alternative path - adding the boot option of HP-UX again.