Vista - KB905866 failed, error code 80070490 in vista update

Hello Members, i hope someone has the answer.

I'm having a major issue trying to get this update to install, somethings
very wrong, i've already read another thread regarding this update, but as
yet no one has the answer.

The computer again is a Dell Inspiron 1720, Intel graphics chipset, 160gig
HD, with 2gig of ram, the Windows Vista SP1 was offered for install a month
ago, and i accepted it.

The system does not have windows defender on it, or running as far as i can
tell in the systray, and i only use Windows live Mail as my email client, the
firewall is handled by McAfee Security center(same as the other members
threads).

I have tried to install the update from a downloaded version, with the same
error, so now i'm hoping a forum member might have the solution, or who to
contact about the issue.

Your help would be very grateful.

Kind regards