Wubi "prefix" is not set

Asked by Abhinav Arora on 2011-09-15

Hello everybody

I installed Ubuntu 11.04 alongside windows using Wubi with a partition of 15gb. I installed it in my G: drive while windows is installed in C: drive Everything was working fine until I installed some updates using the Update Manager.

Now when i select Ubuntu from the multi boot screen, I get the following message:

NTFS5 error "prefix" is not set
Not found; /ubuntu/disks/root.disk
Not found; /ubuntu/install/boot/grub/grub.cfg

Immediately after this message i am directed to a Grub Command line.

Moreover, when i open my ubuntu installation directory from windows, I am unable to find the following folders:


I also uninstalled Ubuntu using add remove program in Control panel and then reinstalled it using Wubi. However after updating i again faced the same problem.

Please Help!!

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bcbc (bcbc) said : #1

If you are getting regular corruption of the \ubuntu\disks directory there may be some hardware compatibility issue. Please list your specs: computer brand/model, graphics card. If the corruption is due to forced shutdowns, please avoid these by trying the options listed here: https://wiki.ubuntu.com/WubiGuide#How_to_reboot_cleanly_even_when_the_keyboard.2BAC8-mouse_are_frozen

For info on how to recover the lost data refer to the following: http://ubuntu-with-wubi.blogspot.com/2011/08/missing-rootdisk.html

PS That 'prefix' not set message is always issued on 11.04 Natty Wubi installs - and does not indicate any problem. The problem you are having is NTFS file system corruption.

Abhinav Arora (abhinav-arora) said : #2

Hi the following are the laptop specifications:

Acer Aspire 5920
Intel Graphics accelerator.

Now I have reinstalled it using Wubi, but this time I am not updating my Ubuntu. So now it is working fine. But as soon as I install new updates, the same errors will appear again.

Is it a problem related to updates?

bcbc (bcbc) said : #3

I can't find any issue with this computer and Ubuntu... so this is a bit of a mystery. You could try a proper dual boot or use a virtual machine (or just don't update as you say, but it doesn't seem an ideal solutio).

Abhinav Arora (abhinav-arora) said : #4

I did the same procedure on a Dell Laptop and then i I updated it. It worked perfectly fine on it without any errors.

Can you help with this problem?

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