Grub bootloader not recognised by old Bios.
Installation of grub 2:
Grub 2 was installed on a 500 GB hard disk with separate home and swap partitions. In the beginning a small partition was left with grub_boot flag to be used by grub for booting. The installation was LinuxMint 15 Olivia. The hard disk was partitioned with GPT and had hybrid MBR table as well. The system return the message ‘No bootable disk’ and refused to boot.
An old machine:
This machine was an old 1.4 gz, core 2 duo Intel, of last decade but in surprisingly immaculate condition.
There was no problem in booting from live CD/USB. Only the installation on GPT partitioned Hard Disk did not boot. We installed boot-repair tool by Yannubuntu. On blindly accepting the recommended fix it installed bootloader on all partitions as also on live USB. On rebooting the system booted Grub 2 but from USB MBR. Trying to boot from hard disk did not succeed. Thus the mistake presented the solution.
Tried to re-edit the MBR table also but it did not work.
Solution to problem:
Attempt to install Grub 2 manually (from terminal) also failed as it aborted with the message ‘/cow’ not found.
It appeared that the problem lied in the old bios which was not able to read the GPT partition table as also the hybrid MBR table. As a workaround the grub boot loader was installed in an old memory card and the small card reader, with memory card in it, was permanently attached to the system. After boot the card was unmounted. So far this is working.