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I'm new to Ubuntu and Linux. And I'm running into a Grub rescue no such device error.

I have an older desktop with two hard drives: 60GB and 500GB (resp. sda and sdb). I think they're PATA. I can't set /dev/sdb in Boot Sequence (probably due to the fact that an older BIOS can't boot from a slave drive).

I've just installed Ubuntu on /dev/sdb2, while I selected /dev/sda as 'Device for boot loader installation' and the swap on /dev/sda6/ (See my related previous question on this site). I wanted to make a dual-boot for Windows XP (SP3) and Ubuntu 14.04. Windows XP is running on /dev/sda2 on a 40GB partition.

So I have put / on /dev/sdb2 and I wanted Grub to be on /dev/sda because I could not set the Boot Sequence in Bios to boot from /dev/sdb which would be necessary otherwise for booting into Grub.

When I was all done with installing Ubunutu from Live DVD, it asked me to 'Reboot Now', so I did. Then an Ubuntu screen appeared, but like only half the size of my 15" monitor in the left upper corner. Then nothing... for over 10 minutes. No reaction to keyboard. So I unplugged the power.

Now I booted again, and pretty soon a grub rescue error appeared:

Error: no such device: 2785cb02-5d56-4a3a-8e69-f6f950b92f0e

Entering rescue mode...

grub rescue>

My question is: How do I get from this to a smooth dual-boot system?

I used Boot-Repair-Disk-32bit already, and ran the 'Recommanded Repair'. But I still encountered the same grub rescue error afterwards. Also running it with 'Advanced Options' and checking 'Place GRUB in all disks', I still get the error.

I did discover that the device mentioned in the error ('no such device') is in fact /dev/sdb2, being the ubuntu partition (or /root partition). This partition showed up in 'FileManager > PCManFM' when running it from the Boot-Repair-Disk. And it showed the same number as the error has.

I remember while installing Ubuntu, and while deleting and making the /dev/sdb2 partition -with mount point /- switching this to 'primary', while the default setting was 'logical'. Could this be of influence?

The Boot-Repair-Disk made a few BootInfo Summeries. I have these url's available (not allowed so may links yet).

Please help me finish this installation. Thnx.

Update: the last Boot-repair info from Comments

share|improve this question
You just need one of the Boot-info reports. But some very old BIOS may not boot from a 500GB drive. You may have the BIOS limit of 137GB. Then you either need all of / (root) fully inside the 137GB limit on the drive (it only needs to be 20 or 25GB) or a separate /boot that is fully inside the limit. You can use the rest of the drive as /home or data partitions. –  oldfred Jul 23 '14 at 3:48
Currently /root is on a 40GB partition /dev/sdb2 –  Follow Jul 23 '14 at 12:51
The Boot-Repair-Disk made BootInfo Summeries. Here are the links: 1. Before running the 'Recommanded Repair' 2. After the first 'Recommanded Repair' 3. After the second 'Recommanded Repair' 4. After running it with 'Advanced Options' –  Follow Jul 23 '14 at 12:52
I just noticed that at he bottom of each summery there's a line that reads: 'Please do not forget to make your BIOS boot on sdb (500GB) disk!' That can't be good. That was my orignal question. I need to have Grub on /dev/sda so it can boot, and give me the option for WindowsXP on /dev/sda2 and Ubuntu on /dev/sdb2. I think at least. –  Follow Jul 23 '14 at 13:11
(I found this on dell community) "There is one trick that you can use to boot from an IDE slave drive, and that is to go to system setup when you start the computer and set Drive 0 to off. In that case the slave will be treated as the master and should allow you to boot from it. In this case perhaps I can boot Ubuntu (although it will not have swap anymore. So I tried, but got a new error: error: unknown file type. Entering rescue mode. Grub resucue> So did not help, and I turned Drive 0 back on. –  Follow Jul 23 '14 at 23:35

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