Hi Julf,

The message means pretty much what it says: "UncorrectableError" is a hard sector failure on the media. This can often be corrected by overwriting the entire disk with, say, zeros: cat /dev/zero >/dev/hda

As part of the overwrite, the drive firmware will fix the errors and try to remap the bad sectors automatically.

But first, it would be good to have a look at the S.M.A.R.T. logs, and run a low-level drive test. The S.M.A.R.T. data may tell WHY the sectors went bad, but most likely it won't.

Under Linux, smartmontools are needed, and the "smartctl" command in particular.

The IBM Drive Fitness Test (self-booting diskette image) does the same stuff, and can also low-level reformat IBM drives.

Cheers