Recently I wanted to try out some software from the repository for Ubuntu 12.1(+): that meant upgrading my workshop machine's installation from 12.04LTS. Whilst the upgrade went smoothly enough, I found Quantal to be a little glitchy and I couldn't get LedgerSMB to work, so I abandoned the project.
Given that the workshop machine should be as stable as possible, I decided to revert the OS to Precise: easy, right?
Slipping the installation disk into the drive and electing to format the partition before (re)installation, resulted in the following error on reboot:
Followed by the grub prompt:
file '/boot/grub/i386-pc/normal.mod' not found
grub rescue >
At first I thought that the install had been corrupted and I tried simply reinstalling the reinstall (if that makes sense), but no joy - the same error appeared on reboot. The good news is that the fix was fairly simple: delete the root partition ("/") and recreate it during the installation process. The bad news is that, if you haven't created a separate home partition (or, if you don't have a full, current backup of your files) everything gets deleted as a result!
Fortunately, I am in the habit of maintaining a separate
/home partition, so my directories and documents were quite safe during the restoration of Precise. However, if you haven't segregated your /home and root directories, try using the install DVD as a live disk and copying your files to an external disk or drive before attempting to repartition your disk (or backup your system) before down-grading.
Sources & References:
- LedgerSMB: Home