Windows 7 - How do I reinstall a failed update?

I had SpywareBlaster running so it caused a cumulative security update for IE9 to fail (I think). I disabled SWB but even when I "check for updates" the failed item no longer shows up. It is listed under Update History and is shown as failed. How would I be able to make it available again through Update?

Don't worry. It will come back by itself. In the next days.

Really? What sort of magic is this?

Well, the MS host scans the systems worldwide for missing updates. How did you think your updates got to your system in the first place.

Even with SWB disabled it could still cause your update to fail. You would need to uninstall it to make sure it does not interfere with updating.
Try using MS Security Essentials instead.
Microsoft Security Essentials - Free Antivirus for Windows

which update was it? see your "update history" and post the full name plz

I was questioning what would make it show up automagically later, when a manual "check for updates" didn't make it appear.

I use both. The gang in the Security forum seem almost unanimous in using both for full protection. MSE is not that strong in up front detection.

I guess it was not your turn yet.

Hmm, usually, in my case at least, a failed update will still show as available in the updates window.