A friend contacted me with a problem booting into Windows. I asked him to boot into Ubuntu and this is what we found. Gparted reported the disk as ‘unallocated’ and ‘Cannot have overlapping partitions’ an ‘fdisk -l’ told me ‘Partition table entries are not in disk order’. The NTFS partition for Windows could not be seen with fdisk – just the FAT of the recovery partition and the extended partition containing the ext4 and swap partitions of Ubuntu. 
He tells me that someone using the laptop that day had been hit by a virus when opening an email. This seems like some pretty aggressive virus but the disk does not appear to be faulty so the shortlist of causes is quite short.
Looks like I will be blowing the partitions away and adding the Windows one again. A perfect opportunity to discover the freedoms and relative safety of Linux?
If he did not have all his data backed up I think I would be resorting to using testdisk etc.
