Here I am, updating some old posts, that I had forgotten about...

Vista Update post

The first one is an update to a one-year-old post about a problem: during Vista SP1 update

Remembering the Issue

The issue was that:

And then Vista tells me it couldn't install my computer because error 0x800F0826.

And I was thinking of waiting for final release to fix it... Of course, it didn't work.

This happens when Vista Ultimate is used on a multiboot machine.

Solution

The solution was to give back the bootloader to Vista Bootloader and not Grub. So, configure again the Vista Bootloader and write changes to disk.

Then reboot and update to Vista SP1.

Reinstore Grub as your main Bootloader using the usual tools :D