|I'm assuming Automatic Update is working fine otherwise - other updates are installing properly. |
How to Hide an update in XP.
(If you haven't been there before, you will be asked to install an ActiveX control, answer Yes, then in IE 7 or 8 you will need to click on the Information Bar that will show up in the bars at the top of the screen so you can give permission to install it, do that, after that do an Express search and you will be asked to install a few files - do that. You may also be asked to Restart the computer - if so, do so, and come back to Windows Update.)
Do a Custom search (finds High Priority and Optional updates),
OR do an Express search if Automatic Update kept popping a message about an update again and again after you had downloaded it, or if you're sure it's a High Priority update oherwise.
Find the update you want to Hide.
In this case...
Find the KB2538242 update in the lists - it's probably in the High Priority listings.
"Security Update for Microsoft Visual C++ 2005 Service Pack 1 redistributable package (KB2538242)"
Expand (show all of) the text for it by clicking on the plus sign in the small box.
Click on the green checkmark that selects the update to remove it.
You will then be able to click on the blank box before Don't show this update again below the text description to insert a checkmark in the box.
If you ever want Windows Update or Automatic Update to reveal a Hidden update again, on the first Windows Update page, choose Show Hidden Updates.