David Both wrote:
The dd command shows you **exactly** what is in the MBR and, if you want, the following sectors. But the following sectors are not particularly relevant to boot. THe MBR contains the boot record and the partition table. There is not room for anything else. But your problem is not with the MBR so the solution does not lie there.
Is this strictly true - that only the MBR is read at boot-time? I have saved and re-inserted the MBR on occasions (not in the present case) and it did not seem to be sufficient. I notice for example that gparted leaves quite a lot more space at the beginning of the disk, as does Windows.
Although you have already reinstalled, you might have recovered by changing the boot order of the hard disks in the BIOS configuration for your computer.
Well, that is more or less what I said - I only realized that was the problem after trying many other solutions. In self-defence I would say that I read half-a-dozen articles on the web telling you what to do if grub fails, and none of them mentioned the possibility that the hard disk order might have been changed - in my case by running the system with one disk removed, and then with the disk back in place.