How do I recover Windows boot capability?
 

I have two partitions Windows XP (which was already installed before Ubuntu) and Ubuntu 9.1 (which I installed later).

Now the XP doesn't boot anymore (sorry but I need it sometimes), the Windows screen with the progress bar appears and then it reboots after a couple of secs.

I can access to the XP partition from Ububtu.

Of course I don't want to damage Ubuntu during the XP recovery action.

Thanks

Did you resize the NTFS partition to get Ubuntu on the machine? It could be that there are errors in the filesystem that is keeping Windows from booting. If that is the case you can boot to the XP install CD, get into the recovery console, and check the NTFS partition for errors that way.

Naturally, Windows will give you no indication as to what the actual problem is, so we are somewhat left in the dark with how to proceed.

Try
os-prober
then
update-grub

Is Ubuntu 9.1 supported?

Yes, Ubuntu 9.10 is still supported, and updating Grub will not solve this problem, since the Windows-bootloader is starting.

Besides from booting from CD you can also try to boot in Safemode. Press F8 immediately after choosing Windows in your bootmenu and pressing Enter. You may have to press the key more than once to activate the boot-menu from Windows. There choose safe-mode and look how far you will get.

Find your Windows CD. Then restore the installation.

Sorry if its not a linux solution, but the Windows CD will help.

I tried that, but if I try to DIR C: I get an error in Spanish that refers to allocating files or something like that ("Error en la numeración de archivos")

Tried that, to the same effrect: Windows reboots.

---------- Post added 03-02-11 at 09:24 AM ----------

But won't the Windows CD restore wipe out the Linux Partition?

Are you trying to get to the Windows 0S? If Windows Shutdown improperly, it will give you trouble booting normally. If it does go thru a disk check, try to let it finish.

If you don't have one of those recovery discs, but a real Microsoft CD, you can boot to the repair-console and try to repair your Windows from there, or you can try a repair-installation. This will not erase your Linux-partition, but it will replace the bootloader with the one from Windows. It is not that hard to repair that, so I would recommend to try that, and if it works we will guide you through the re-installation of your Linux bootloader.

Warning: Before going any further, make sure that you have backed up all your important/valuable data, from both systems, Linux and Windows. You can use your Linux-installation or a live-CD for that.