Hi José.
There is a special group for trouble with Windows Updates.
On the web:
http://www.microsoft.com/communities/newsgroups/en-us/default.aspx?dg=microsoft.public.windowsupdate
In your newsreader:
news://msnews.microsoft.com/microsoft.public.windowsupdate
Anyway...Something might interfere with the update such as an
Antivirus or Antispyware software. Can you go to Controlpanel-->Add
or Remove program and put a check-mark in the "Show updates" radio
button. See if you can find the update that is repeatedly offered and
chose to un-install it. Reboot if it state it has to.
Then in Internet-options in the Controlpanel chose to clean History,
Delete files and check also Offline content and then clean Cookies.
Temporary disable Antivirus and Antispyware software and try getting
that update again by going to the Windows Update site. Come back if
nothing gets better with the text from that particularly update log
file. You can find it in C:\Windows\ KBnumber.log
Hope this helps.
Kind regards,
Gunilla.