I had installed Ubuntu 9.04 on twp previous occassion and on both, after working for about a week, I got a GRUB Error and I reluctantly switched back to Windows.

Now I wish to switch back to Linux. One query - Do I need to set my HDD Aceess Mode to LBA (my BIOS has 2 options - Auto & Large and is currently set to Auto)before installing Ubuntu?

Regards

Probably not...

If you leave the BIOS setting at "Auto", you should see if the BIOS is indeed configuring the HDD for LBA in the POST messages. You can check by pressing the "Pause" key to freeze POST so you can read the POST text. If LBA is not noted, what is noted?

Is the BIOS setting "Auto" and "LBA/Large" or just "Large" How old is the system/motherboard and how large is the HDD?

You can change the BIOS to Large, which is not the same as LBA, but you may have to configure GRUB to respect the old 1024 cylinder limit. You might google; I can't remember.

LBA is not a problem for linux.

Could it be that a failure by the BIOS to present the HDD consistently to Grub as an LBA HDD when Grub was configured for LBA was the cause of your GRUB problem?

Do you have the latest BIOS?