“Colin Watson, one of the Ubuntu developers, published in his blog information about Windows applications making GRUB 2 unbootable. Users of dual-boot Windows/Linux installations may face the problem, which boils down to particular Windows applications (Colin does not name them, but users point at least to HP ProtectTools, PC Angel, Adobe Flexnet) blindly overwriting hard disk content between the MBR and the first partition destroying information already stored there, in this particular case — the ‘core image’ of GRUB 2 (GRand Unified Bootloader) making the system unbootable.”
The Windows bootloader sequence is real short. where the first 512 bytes contains the partition info and the bootload code, typically on a windows machine the bootcode simply locates c: and runs the program ntloader.exe or on proprietary systems runs chknt from the system-restore partition.
There are a number of programs out there for windows that know a regular windows install only uses the first 35 bytes of the bootcode so they hide
their info after that point. HP-validate, Acer-isreal, MDG-truechk are three which used to do it for XP and Vista. I’m sure there are others out there as well. I remember doing a system that blindly stored info at the top of partition sda1 and marked the block bad to prevent any chance of resizing the drive. Of course, such efforts failed. I simply did a validation check of the drive which returned the block back to good status, resized the drive and observed that on the next reboot the OS again marked a block bad at the top of the new resized drive.
On 2010-08-29 21:06, please try again wrote:
> oldcpu;2213740 Wrote:
>> I don’t know much about this, but I am wondering if perhaps all
>> developers are to blame (both MS-Windows apps and Grub2 developers ).
> Companies which (intentionaly) bypass the filesystem and install
> (apps)software on the first track are to blame. Macromedia use to do
> that too with an older version of Flash.
Well, grub does just that, so the grub people are also to blame here. Lilo did not use this method,
but then it needed an up-to-date sector map to find himself.
Cheers / Saludos,
Carlos E. R.
(from 11.2 x86_64 “Emerald” GM (Minas Tirith))